The Importance Of Clock Reaction

The Importance Of Clock Reaction
A clock reaction is where the fusion of various reagents, with relation to time, cause a colour change
in the solution. The end of the reaction rate is measured by the increase in the rate of concentration.
There are two factors which contribute to the rate of the reaction, induction and inhibition. Induction
is where the production rate of the clock chemical increases as the increases as the concentration of
the solution increases. Whereas, Inhibition is where the chemical reacts with the clock chemical,
increasing the concentration. The increase in the rate can only occur if all of the inhibitor chemical
is consumed within the reaction (S.J Preece, 1999). Some examples of clock reactions are the
arsenic (III) sulfide clock reaction, and Landolt iodine clock oxidation of bisulphite by iodate. This
specific reaction is stated to be one of the most favourable clock reactions, showing a deep blue
colour within a matter of seconds. This specific reaction involves two colourless solutions that mix
together after a certain amount of time it yields a blue colour change. The chemical equilibrium is a
formula used to describe the rate in reverse reactions. Chemical Equilibria: Rate = k [A]^p [B]^q
The rate law will also be used to analyse the concentrations, and to determine whether the reaction is
zero order, first order or a second order reaction. Secondary data obtained from another investigation
was rate = k[IO3] 1 (Lyle, Department of Chemistry). A
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Chemical Kinetics: The Iodine Clock
Chemical Engineering Department
FIRST YEAR LABORATOY REPORT #1
Name: Shams Alizada
Experiment Title: Chemical Kinetics: The Iodine Clock Experiment Date : 13 October 2016
Submission Date: 20 October 2016 Supervisor: Rashid Akhundov
Contents
Synopsis 2
Introduction. 3
Safety Precautions. 3
Theory 3
Experimental Technique 4
Equipment and Apparatus. 5
Experimental Procedure. 5
Results 6
Discussion 7
Conclusion 8
References 8
Synopsis
The experiment concerning the iodine clock reaction was carried out to find ... Show more content
on Helpwriting.net ...
Lime or soda must be poured on the contaminated floor and it must be cleaned until the floor gets
dry. While using pipette during an experiment, the starch solutions must be pipetted using the rubber
suction bulb, the solutions must not be pipetted by mouth. After checking the color and time, all the
solutions must be disposed in the aqueous residue bottle.
Theory
Iodine Clock is the reaction which includes the colorless compounds and after mixture, observance
the appearance of color in the solution: dark blue/purple. The color, depending on the temperature
and the concentration of the substances which react with one another, appears in a short time

interval. Rate of reaction for the experiment is calculated in the equation given below: reaction
rate=k×〖[A]〗^m×〖[B]〗^n
Here, m and n are called –reaction order, k is called– rate constant which depends on temperature.
There are the factors that can have impacts on the reaction rate of the compounds. As mentioned in
the collision theory (John Green & Sadru Damji), (Green, 2014) these factors involve the
concentration of substances. This experiment will also determine the concentration of H_2 O_2 on
iodide

Abstract Of Cyclic Voltammograms
Fig. 3. Cyclic voltammograms (A) and Nyquist plots (B) recorded at bare GCE (a), β–
Ni(OH)2/GCE (b) and β–Ni(OH)2@CDs/GCE (c) in a 0.1 M KCl solution containing 5 mM
Fe(CN)63–/4–. Inset of Fig. 3B: Equivalent circuit applied to fit impedance measurements, where:
Rs is the resistance of electrolyte solution; Rct is the charge transfer resistance, W is warburg
impedance and CPE is constant phase element.
3.5. Electrocatalytic oxidation of nitrite on the modified electrode
The electrocatalytic activity of the β–Ni(OH)2@CDs/GCE toward nitrite was studied by recording
cyclic voltammograms from the range of potential 0.3 to 1.1 V in the absence (a) and presence (d) of
100 μM nitrite, and compared with other different electrodes such as β–Ni(OH)2/GCE and bare
GCE. As can be seen from Fig. 4, there is no well defined peak on bare GCE, which may be due to
the sluggish electron transfer process in GCE. At β–Ni(OH)2/GCE, the weak peak appears at 0.96 V
related to oxidation process of NO2− to NO3− according to the following reaction:
NO2− + H2O NO3− + 2H+ + 2e− (8)
In addition, no evidence of peaks was found at β–Ni(OH)2@CDs/GCE in the absence of nitrite,
while after adding 100 µM nitrite into the phosphate buffer solution (pH 7.0), an obvious
irreversible oxidation peak at about 0.82 V is observed (curve d), which is 140 mV negatively
shifted compared with β–Ni(OH)2/GCE. Furthermore, the oxidation peak current on β–
Ni(OH)2@CDs/GCE is larger than that on β–Ni(OH)2/GCE. This indicated that the large effective
area of electrode resulting from high conductivity and high surface area of CDs, as well as the
synergistic effects of β–Ni(OH)2 and CDs improve the catalytic behavior toward the oxidation of
nitrite.Fig. 4. cyclic voltammograms (CVs) of the bare GCE (b), β–Ni(OH)2/GCE (c), and β–
Ni(OH)2/CDs/GCE (a, d) in the absence (a) and presence of 100 μM nitrite (b, c, d) recorded in 0.1
M phosphate buffer solution (pH 7.0) at the scan rate of 50 mV s−1.
Effect of pH solution
The effects of the solution pH on the peak current and potential for nitrite oxidation using β–
Ni(OH)2/CDs/GC electrode were investigated by 0.1 mol l−1 phosphate buffer in the pH range of
1–10. As shown in Fig. S2, the current responses

Comparative Evaluation Between Mathematical Models For...
COMPARATIVE EVALUATION BETWEEN MATHEMATICAL MODELS FOR DRUG
RELEASE OF CURCUMIN LOADED MULTIFUNCTIONAL ALBUMIN NANOPARTICLES
Abstract:
Curcumin loaded albumin nanoparticles were employed for intra–tumoral chemotherapy for
treatment of solid tumors1. Drug release study for Curcumin was monitored in–vitro using dialysis1.
The drug release data was fitted into 5 mathematical models such as zero order, first order, Hixen–
Crowell, Higuchi release and Korsmeyes–Peppas release kinetics model. R2 coefficient was
compared and was concluded that Higuchi release kinetics model is best suited for the drug release
kinetics for Curcumin.
Introduction and Significance:
Nanoparticle formulations have found extensive applications as drug delivery ... Show more content
Analysis:
Drug release data for curcumin was fitted into 5 mathematical models and studied to determine the
best mathematical model. The model chosen were:
i. Zero Order Kinetics
The zero–order kinetics depends upon the initial concentration of the drug loaded on the
nanoparticles and refers to constant release of drug5,6. Zero order kinetics is represented as:
Qt=Qo+k*t
Qt = amount of drug dissolved in time t, Qo=initial amount of drug, k=zero order kinetics constant
ii. First Order Kinetics
The release of the drug which followed first order kinetics can be expressed by the equation7: log C
= log C0–Kt / 2.303
Co is the initial concentration of drug, k is the first order rate constant, and t is the time
iii. Hixon–Crowell Release Kinetics
Hixson and Crowell derived the equation: Q01/3–Qt1/3 = κ*t where Q0 is the initial amount of
drug, Qt is the remaining amount of drug at time t and κ (kappa) constant incorporates surface
volume relation. The equation describes the release from systems where there is a change in surface
area and diameter of particles or tablets9.
iv. Higuchi Release Kinetics

Higuchi drug release kinetics model was proposed Higuchi in 1961 based on a matrix system8. The
matrix model is based on initial drug concentration in the, instantaneous drug

Surface Area to Volume Ratio and the Relation to the Rate...
Surface Area to Volume Ratio and the Relation to the Rate of Diffusion
Aim and Background
This is an experiment to examine how the Surface Area / Volume Ratio affects the rate of diffusion
and how this relates to the size and shape of living organisms.
The surface area to volume ratio in living organisms is very important. Nutrients and oxygen need to
diffuse through the cell membrane and into the cells. Most cells are no longer than 1mm in diameter
because small cells enable nutrients and oxygen to diffuse into the cell quickly and allow waste to
diffuse out of the cell quickly. If the cells were any bigger than this then it would take too long for
the nutrients and oxygen to diffuse into the cell so the cell would probably not ... Show more content
The larger blocks have a smaller surface area than the smaller blocks. The smallest block has 1.2mm
squared of surface area for every 1mm cubed of volume. The largest block only has 0.2mm squared
of surface area for each 1mm cubed of volume. This means that the hydrochloric acid is able to
diffuse the smallest block much faster than the largest block.
When the Surface Area/Volume Ratio goes down it takes longer for the

Rate Law Lab
The objective of this experiment was to determine the rate law for a chemical reaction between
crystal violet and hydroxide. A rate law is a part of kinetics, which is the study of how fast reactions
occur and how to control the rate of a reaction (4). The rate law is be determined by measuring and
graphing the absorbance of reactants during the reaction. The reaction was first order with respect to
crystal violet (CV+) and hydroxide (OH–). Since crystal violet is in much smaller concentration
than hydroxide, the experiment captured the reaction rate and order of crystal violet while the order
of OH was calculated post–lab using the pseudo first order method (eqn 1,2,3). The rate law for
CV++OH– CVOHis Rate = 0.1644m–1s–1[CV+][OH–].
Introduction
Kinetics is the study of how fast reactions occur and how to control that rate. The rate of a reaction
is defined by the change in concentration of reactants and products over time (4). The rate law for
this reaction is Rate = k[CV+]m[OH–]n, where m is the order with respect to CV+, n is the order
with respect to OH–, and k is the rate constant. Because the concentration of OH is so much larger
than the concentration of CV+, only [CV+] will change when significantly, which is why the
experiment only focuses on the change of concentration in crystal violet while the concentration ...
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A rate law is a mathematical equation that describe the rate of a reaction. A reaction rate is the
change in concentration of reactants or products over time (3). A Vernier colorimeter was used to
measure the absorbance (or concentration) of CV+ when mixed with OH. The concentration of CV+
generally decreased over time at a similar rate when mixed with 0.1M and 0.2M hydroxide. The data
was copied into Excel then made into

Chemical Reaction Lab
Valdez 1
Ariana Valdez
Mrs Mcnamara
Chemistry 1st hr
May 31, 2017
Reaction Rate with Concentration and Temperature
According to The Kinetic Molecular Theory
The reaction rate is defined as, the speed at which a chemical reaction proceeds. It is often expressed
in terms of either the concentration (amount per unit volume) of a product that is formed in a unit of
time or the concentration of a reactant that is consumed in a unit of time (according to Britannica
Online Encyclopedia). But not only concentration affects the reaction rate, temperature also affects
the rate. The Kinetic Molecular Theory is described as a gas that has a large number of
submicroscopic particles (atoms or molecules), all of which are in constant rapid motion that has
randomness raising the collisions with each other and with the walls of the container. All chemical
reactions proceed in different ways according to their reacting substances, types of chemical
transformation, and temperature. In this lab, we tested the effects of ... Show more content on
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Changing the concentration affects how many particles of the substance that are needed in the
chemical reaction. The reaction rate can be increased if the concentration of reactants is raised
(according to www.2.chem,uic.edu). When you increase the concentration you are also increasing
the number of particles, this causes for there to be more chances of collisions between molecules
when you mix the two substances. When lowering the concentration and adding something like
water to your solution A, you decrease the number of particles of substance A and therefore there is
a less likely chance that the particles in substance A will collide with substance B because there is an
increase of water molecules that will collide with substance

Reaction Rate Of Clock Reactions
Introduction:
Investigations into the mechanics of chemical kinetics can reveal invaluable information relating to
the rates of reaction. There are numerable applications of reaction rates, knowledge in this area is
pivotal for industrial, commercial and research sectors. Thus, allowing them the ability to
manipulate a variety of factors of chemical reactions with the use of reaction rates. In the scope of
the kinetics of clock reactions, there is a range of information that can be obtained about reaction
rates (Shakhashiri, 1992).
A clock reaction is characterised by an abrupt colour change following an established time lag
(Lente et al, 2007). The induction period in a clock reaction is a result of low concentrations of the
clock chemical (i.e. the chemical that enables the final reaction). The induction period ends after the
total consumption of a limiting reagent, which initiates a short increase in the rate of product
formation, resulting in a visible colour change (Schmitz, 2010)(Lente et al, 2007). The reaction rate
of clock reactions is subject to factors including temperature, concentration, catalysis and inhibition.
These factors can be manipulated, thus changing the length of the induction period in a 'clock–like'
manner (Shakhashiri, 1992).
Changes in the rate of reaction can be described in terms of chemical equilibrium. "Chemical
equilibrium is a state in which the forward and reverse reactions take place at the same rate"
(Wilbraham et al, 2002). The

Landolt Iodine Clock Lab Report
The importance of conducting this experiment is to discover the rate reaction of the Landolt Iodine
Clock. This reaction is used to display the chemical kinetics in action, it was discovered by Hans
Heinrich Landolt in 1886. It is where two colourless solutions are combined and no instant change
appears but over a certain time delay depending on the factors it will instantly change to a dark blue.
The Chemical kinetics of the reaction refers to the rate of the reaction. Different reactions occur at
different rates, for example if it is a proton transfer reaction which is an acid–base reaction it will
often occur at a faster rate. When the molecules collide in the reaction they must have a sufficient
amount of kinetic energy so that the reaction can be initiated. The amount of kinetic energy is
generally dependant on the temperature of the reaction, at higher temperatures there is a higher rate
of reaction because of the increase of kinetic energy in the reactant molecules. The arrhenius
equation was formed in 1899, by chemist Svante Arrhenius it was from a combination of activation
energy and the distribution law. The arrhenius equation is used in science to calculate the
relationship between the rate of a reaction and its increase or decrease in temperature. If a reaction
has higher temperatures with low activation energy it tends to favour increased rate constants. The
equation is in relation to k, which refers to the rate constant in any given equation. With the

What Are The Factors That Affect The Rate Of Reaction
ABSTRACT
The purpose of this investigation was to identify and investigate the relationship between various
factors and the rate of a reaction. The reaction that was tested, used the combination of a potassium
starch solution mixed with a sodium solution, commonly known as the 'Iodine Clock Reaction'. The
two clear solutions are mixed together, which after a given time will form a dark blue solution. The
factors used in this investigation are the concentration of two substances and the temperature at
which the reaction occurred.
BACKGROUND INFORMATION
Kinetics is essentially the study of reaction rates and how they can be affected. Factors such as
concentration, pressure, temperature, and enzyme activity, are commonly tested regarding their
impact on the rate of a reaction (Khan Academy, 2017). It is important to recognise and understand
the components that affect the rate of chemical reactions as this allows control over the reaction
process.
Chemical reactions progress naturally at different rates. A chemical reaction involves the
rearrangement of the molecular or ionic structure of substances as they change into other substances
by the breaking of bonds in reactants and the formation of bonds in products (Wilbraham, 2002).
Collision theory can be used to explain why chemical reactions proceed at different rates. Collision
Theory states that atoms, ions and molecules must collide in order for a reaction to proceed and
form products (Stubbings, 2017). Thus, the

The Physics Of Chemical Kinetics
Investigations into the mechanics of chemical kinetics can reveal invaluable information relating to
the rates of reaction. There are numerable applications of reaction rates, knowledge in this area is
pivotal for industrial, commercial and research sectors. Thus, allowing them the ability to
manipulate a variety of factors of chemical reactions with the use of reaction rates. In the scope of
the kinetics of clock reactions, there is a range of information that can be obtained about reaction
rates (Shakhashiri, 1992).
A clock reaction is characterised by an abrupt colour change following an established time lag
(Lente et al, 2007). The induction period in a clock reaction is a result of low concentrations of the
clock chemical (i.e. the chemical that enables the final reaction). The induction period ends after the
total consumption of a limiting reagent, which initiates a short increase in the rate of product
formation, resulting in a visible colour change (Schmitz, 2010)(Lente et al, 2007). The reaction rate
of clock reactions is subject to factors including temperature, concentration, catalysis and inhibition.
These factors can be manipulated, thus changing the length of the induction period in a 'clock–like'
manner (Shakhashiri, 1992).
Changes in the rate of reaction can be described in terms of chemical equilibrium. "Chemical
equilibrium is a state in which the forward and reverse reactions take place at the same rate"
(Wilbraham et al, 2002). The relative

The Demonstration And Variance Of The Iodine Clock Reaction
The demonstration and variance of the iodine clock reaction displays principles of equilibrium, and
rate of reaction, all affected by change in concentration and temperature. In order to properly
examine rates of reaction, one must first understand the principles of chemical kinetics. Reaction
kinetics deals with the rates of chemical processes; that is the behaviour of particles within a
solution. The study of chemical kinetics is of upmost importance in chemical research, as it is a
powerful tool for determining the reaction mechanism (scilearn.sydney.edu.au). In order to
determine this mechanism, we must identify the elementary steps within the reaction itself.
Any chemical process may be broken down into elementary processes, or ... Show more content on
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Reaction Rate
Speed of a chemical reaction may be defined as the change in concentration of the products per unit
time. (chem.libretexts). A rate law expresses the reaction rate as a function of the concentration of
each reactant. The rate at any instant is proportional to the product of the molar concentrations of the
reactants, each concentration raised to an experimentally determined exponent. For a general
equation of the form aA+bB = cC + dD; the rate law is in the form
Rate= k[A]ˣ [B]ʸ . Many reactions, like the Landolt Iodine clock, have multiple steps, and therefore
the exponents do not necessarily correspond to the coefficients of the overall equation, as is
traditionally the case with rate law calculations. The reaction order is the exponent to which the
concentration of that species is raised, and it indicates to what extent the rate affects the rate of
reaction, as well as which species has the greatest effect (chem.libretexts, 2017). In order to
calculate the order of the reaction, graphs can be plotted under the principles of the integrate rate
law. This can be done with the recorded concentration and time values, obtained via our
experimental procedures.
The rate law for a first order reaction is known as rate = – dy/dx = k [A]. which integrates to give:
ln[A]= –kt + ln[A] ₀.
This form is useful because of its parallel to the linear equation: y = mx + c

Chemical Reaction On Chemical Kinetics
Olivia Isaacs
C127
15 November 2014
Chemical Kinetics
Objective:
This experiment runs many reactions varying the concentrations of the reactants in order to
determine the order for each component and the rate constant.
Introduction:
Chemical kinetics is the study of how fast a chemical reaction occurs and the factors that affect the
speed of reaction.1 Reaction rates are the measure of how much the concentration of reactants
change during a given reaction.1 The rate of change of the reactants, Rate = – Δ [X]/Δt, is related to
the slope of the concentration vs. time graph.1 From observing reaction rates, the overall order of
the reaction and the rate constant can be calculated by using the integrated rate laws. For a zero–
order reaction, the rate law can be written as [A]t = –kt + [A]0, where [A]t is the concentration at a
given time, k is the negative slope, t is the time, and [A]0 is the initial concentration.2 Using the
same variables, a first order reaction can be written as ln[A]t = –kt + ln[A]0 and a second order can
be written as 1/[A]t = kt + 1/[A]0.2 On a graph, these concentrations are plotted vs. time, allowing
the R2 value and equation of the line to be calculated. The R2 value is used in determining the order
of the reaction. The closer the R2 value is to 1, the more likely that the graph displays the correct
reaction order. The y=mx+b equation provides information about the slope and y–intercept, essential
when determining the order and rate constant.

Lab Report On Kinetics Of Alcohol Oxidation
Lab Instructor's Name: Zhen Qiao
Student's Name: Nhu Duong
Section # CHEM 102 – 110
Experiment #6
Date of the experiment: 01/29/2016
Title: KINETICS OF ALCOHOL OXIDATION
Drexel University Winter 2016
Introduction:
This report concerns the experiment of determining the order of reaction and the kinetic rate
constant of alcohol oxidation. This experiment relates to the knowledge of chemical kinetics, the
application of Beer's Law, and other calculations.
Chemical kinetics involves the examination of reaction rates, which are the speeds of chemical
reactions. There are chemical reactions which proceed in long periods of time as well as chemical
reactions proceeding in short periods of time. Regarding reaction rates, the reaction order and
kinetic rate constant are considered.
Take a general reaction in solution for instance: aA+bB⇌Product(s) The reaction rate is calculated
using the following function: rate=k〖[A]〗^x 〖[B]〗^y
Where [A] and [B] are the concentrations of A and B in the solution, unit: mol/L or M; x and y is the
reaction order of A and B respectively; k is the kinetic rate constant, its unit depends on the order of
the reaction.
The values of x and y are the partial order corresponding to A and B. The sum of x and y is the
overall reaction order. The values of x and y can be either negative or positive. They can also be
either integer or fractional. The reaction rate can be understood as how fast the reactants are
consumed or how fast the

Investigating The Effect Of Ligand On The TFT Properties...
To investigate the effect of ligand on the TFT properties, we focused on the In2O3 NCs films cured
at 150 °C. Both the ligand molecules OA and BET were conserved on the NCs surface in the TFT
devices at a curing temperature of 150 °C. The TGA curves confirmed no weight loss at 150 °C
(Figure. 4). Moreover, the FTIR spectrum of the thin films cured at 150 °C also supported the
existence of the ligand molecules OA and BET with high intensity peaks of the alkyl group Csp3–H
and carboxylate group COO– (Figures 5(a) and 5(b)). Therefore, The µ increased after the ligand
exchange process because of the decrease ligand length from OA (1.97 nm) to BET (0.48 nm). In
the In2O3 NCs films cured at 150 °C, the NCs are separated by insulating ligand OA ... Show more
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Table 1. TFT characteristics of the In2O3–OA NCs and In2O3–BET NCs thin films annealed at
different temperatures.
The µ of In2O3–OA NC and In2O3–BET NC thin films increased by 2–4 orders of magnitude with
increasing annealing temperatures from 150 °C to 350 °C, at which the OA or BET ligands
decomposed as discussed in the TGA (Figure 4) and FTIR results (Figures 5(a) and 5(b)). Specially,
the highest mobility obtained in this study are 4.1 cm2V–1s–1 for the In2O3–BET NC TFT
annealed at 350 °C. This can be explained by thermal decomposition of the organic ligands OA or
BET on the NC surface, decreasing the d between the neighboring nanocrystals with increasing
annealing temperatures [15]. This was further supported by investigating the crystalline domain
sizes of the NCs from the XRD pattern of the thin films (in the supplementary information). The
crystalline domain sizes were not significantly affected by the annealing temperature, indicating that
the In2O3 NC thin films still consisted of an assembly of the single crystalline NCs [15].
Temperature dependence of In2O3 NC TFT devices To know the charge transport mechanism, the
relationship between the mobility and temperature was investigated. The temperature dependence of
the mobility takes the general form

Gravimetric Determination of Calcium
Gravimetric Determination of Calcium ABSTRACT Determining the mass of a pure compound is a
method of a gravimetric analysis. One of the gravimetric analyses is the precipitation; it is a method
of separating the analyte from the unknown sample as a precipitate where it will be filtered and
converted into a known composition that can be weighed to determine its mass (Skoog et al, 2013).
Determining the mass of calcium by using gravimetric analysis was the objective of the experiment.
A 25 mL of unknown sample was used to analyze its calcium component. This sample was diluted
with 25mL of distilled water in a beaker. It was converted into a soluble precipitate by adding 25 mL
of ammonium oxalate solution and 15 g of solid urea. Since ... Show more content on
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We made sure to rinse the glass rod before removing it to the beaker. Then we added up 15 g of
solid urea to each sample. We boiled the solution for 30 minutes up until the indicator turns yellow.
After boiling, we filtered it each through a funnel. The remaining solid from the beaker will be
transfer to the funnel by adding 3mL of ice cold water to the beaker. We made sure that all of the
precipitate has been transferred. After that, we used 10 mL of ice cold water to rinse each beaker and
pour the washings over the precipitate. We transferred the precipitate in to the petridish, but before
that we weighted first the petridish with the filter paper so that we can get the grams of the CaC2O4
2H2O precipitate later. We dried the precipitate in an oven set at 105oC for 1 hour. After that, we
placed it inside the desiccator for 30 minutes to cool down the heat. Then instantly we weigh the
petridish with CaC2O4 2H2O precipitate. In order to get the weight CaC2O4 2H2O precipitate, we
subtracted the mass of the petridish alone from the mass of the petridish with CaC2O4 2H2O
precipitate. And for determining the weight of Ca in the CaC2O4 2H2O precipitate, we use
stoichiometry. We also computed for the average weight of calcium. III. RESULTS AND
DISCUSSION Sample No. Trial 1 Trial 2 Volume of sample analyzed, mL 25 mL 25 mL Weight of

Investigating The Reaction Rate Of Crystal Violet
orah Albaiz
CHMY143–016
Katie Link
Lab Partner: Lydia Aman
Crystal Violet Kinetics
Purpose:
The purpose of this experiment was studying the reaction rate of crystal violet with NaOH by
observing the concentration using the MicroLAB colorimeter, monitoring how the reactant
concentration affects reaction rate constant, determining the reaction order, and to calculate the
reaction pseudo rate constants and the true value rate constant. The rate of the reaction of crystal
violet with NaOH is given by the generalized rate law, rate = k [OH–]x [CV]y where k is the rate
constant for crystal violet and CV is crystal violet, C25H30N3+. Where x and y are the reaction
orders. The equation can be rewritten as:
Eq.1 k' = k[OH–]x
Since solutions of crystal violet obey Beer's law, absorptivity can be calculated using the following
equation:
Eq.2 At = ε l[CV]t
Where A is the initial absorbance when the experiment first starts, l is the path length of the cuvette
(2.54 cm), and [CV]t is the initial concentration of crystal violet.
Procedure:
Determination of Reaction Order in Crystal Violet
MicroLAB Kinetics program was opened, then the colorimeter was calibrated to a 100%
transmission by filling a marked, clean, clear cuvette, about ¾ full of deionized water. The cuvette
was wiped with a Kimwipe from the outside before putting it in the colorimeter. The cuvette was
inserted in the chamber, then the cap was closed, and the Read Blank button was clicked to start the
calibration.

The Importance Of Chemical Kinetics
Chemical kinetics studies and determines the rate or speed at which chemical or physical processes
occur (Oliver,n.d.)(Jircitano, n.d.). The rate of reaction is the speed at which the reactant in a
reaction transforms into products or the change in concentration of a chemical species over the time
taken for that change to occur (Oliver,n.d.)(Jircitano, n.d.)(Mack, n.d.)(Blackburn,n.d.). Chemical
reactions occur at many different rates and in aqueous or equilibrium systems this rate is dependent
on the variables such as the reactivity of reagents, initial concentrations, temperature induced
fluctuations and any means of catalysis. (Oliver,n.d.)(Jircitano, n.d.)(Blackburn,n.d.). In order to
measure rate the change in concentration in a particular reaction must be determined as well as the
time of which this occurred. However studying the concentration at any time during a reaction is
problematic since the reaction must be stopped and a sample must be removed both which
negatively affect accuracy. One class of reactions that enables the change in concentration to be
observed at a particular time is clock reactions. Ina clock reaction an initial induction phase precedes
a significant change in concentration of a particular species. (Preece, King, Billingham, 1999). The
rapid increase in concentration results in significant effects such as dramatic color change. There are
two types of clock reaction: 1. Induction where as small concentration grows till it results in

Rate Law Lab Report
Discussion Since the rate law was determined to be first order, as seen in equation 2, the rate of
reaction, the rate at which the concentrations of the reactants decrease, was linear. Which means the
reaction depends linearly on only the concentration of bleach. This experimental rate law was the
same as the literature rate law for the bleaching reaction between green dye and cetylpyridinum
chloride, with first order dependence on the bleaching compound cetylpyridinum chloride. Even if
the literature reaction was not parallel to the one studied in this report, it still served as an adequate
model reaction for comparison.3 Therefore, the experimental rate law processes some degree of
accuracy. Rate laws are used to define the rate of reaction ... Show more content on Helpwriting.net
...
When compared to a similar literature reaction, the rate laws matched, both depended linearly on
only the concentration of the bleacher reactant. Which means the experimental rate law has a level
of accuracy. The activation energy of the bleaching reaction was determined to be 12328 J/mol,
much larger compared to the similar literature reaction's value of 7580 J/mol. This difference in
activation energy could have been due to bleach processing inferior oxidizing capabilities, or many
other differences between the

Investigating Temperature On Rates Of Reactions
INVESTIGATING TEMPERATURE ON RATES OF REACTIONS
STRAWBERRY KWAN, Yousof Nowrozi, Selena Ferguson, Isaac Kambouris, Lynn Peng, Elliott
Jones–Perrin CONTENTS
INTRODUCTION 3
BACKGROUND INFORMATION 4
AIM 9
HYPOTHESIS 10
APPARATUS 10
PROCEDURE/METHOD 11
VARIABLES 12
RISK ASSESSMENT 14
DIAGRAM 15
RESULTS 16
DISCUSSION 16
CONCLUSION 19
REFERENCES 20
BIBLIOGRAPHY 20
APPENDIX 21
INTRODUCTION
Rate of reactions play a vital role in real life situations. Everyday situations, such as cooking,
require reaction rates to be increased. To bake some cookies, you place them inside an oven. But
why is that? Well, placing the cookies in the oven speeds up the rate of the reaction by heating it up.
When the cookies have more heat energy, they cook faster. Additives may be added to foods to
speed up the reaction. These are called catalysts. Likewise, we place milk in our fridges to slow
down the reaction rate by removing heat and preventing the milk from going bad. This is because
the milk would turn sour if we left it out near a window. (14)
Enzymes are used to speed up biological reactions. When digesting food, enzymes are used as
biological catalysts to speed up metabolisms. Excess heat from this is used to regulate the
temperature of endothermic animals' bodies. When a person is ill, their body temperature increases
as heat fights bacteria by slowing down the rate of bacteria production. Respiration is another
example of when reactions are sped up in biological systems. Rates of reactions

Reaction Rate Of Reaction
Background: A clock reaction generally involves a mixture of solutions that, after a certain amount
of time, displays a sudden colour change. This process demonstrates chemical kinetics in action,
which is the study of chemical processes and rates of reaction where the reaction rate is the speed at
which the chemical reaction proceeds. It is dependent on several factors that rely on one basic
underlying principle called collision theory. In order for a reaction to occur, the reactant molecules
must collide with each other with a certain minimum energy called the activation energy to break
and form the appropriate bonds as well as have the correct orientation when colliding. If the
favourable amount of collisions increase, then the rate of the reaction would increase. However, if
the reactant particles do not collide frequently or collide with less energy than the activation energy,
they bounce apart and the reaction would then proceed slowly or not at all. Concentration is one of
the factors that affects reaction rate. Raising the concentration of the reactants, alters the number of
particles per unit volume. Thus the more molecules present in a given volume, the greater the
probability of them colliding. If they have energies equal to or greater than the activation energy, a
higher concentration would therefore result in an increase in the reaction rate. The opposite is true if
there is a lower concentration of reactant molecules.
The relationship between rate and

Chemical Kinetics Lab Report
Chemical kinetics is based on the use of an experimental rate law to determine the mechanism of a
reaction. The experimental rate law for the given experiment can be found through the experimental
instantaneous initial rate and the concentrations of each of the reactants present. First, using the
equation rate = k[A]n[B]m, a ratio can be created of the rate equation of trial 1 to that of trial 2.
These two trials are chosen because the concentration of reactant A is the same for both trials, so it
can be simplified to one in the ratio. Since k is a constant and thus the same in both trials, it can be
simplified to one in the ratio as well. After exchanging variables for the experimental data and
simplifying, the resulting equation is 0.5 = 0.5m, ... Show more content on Helpwriting.net ...
This yields the equation 0.25=0.5n, which produces the result n=2, which is the order of reactant A
in the rate equation. Thus, the experimental rate law is found to be rate=k[A]2[B]1. Since n and m
denote the order of the reactant, reactant A is second order and reactant B is first order in the rate
law. The overall reaction order for the rate law can be found by adding n and m, and is found to be a
third order reaction. However, this reaction is not an elementary reaction, as the coefficient of both
reactant A and reactant B in the equation is 2, so n and m would both have to be 2 as well for the
reaction to be elementary. Since reactant A is second order, the 1/[A] vs. time integrated rate law
plot will yield a straight line, as taking the time integral of the rate law yields a linear equation if an
inverse function of [A] is used. Since reactant B is first order, the ln[B] vs. time integrated rate law
plot will yield a straight line, as taking the time integral of the rate law yields a linear relationship
between time and [B] if a natural log of [B] is

Rate Equation And Order Of Reactant
Rate equation and order of reactant:
The rate of reaction is defined as how fast the reactant is converted to the product and it is measured
in moldm–3s–1
Rate=(change in concentration(〖moldm〗^(–3)))/(time taken (s)) , the unit of rate = moldm–3s–1
Rate = k [A]x [B]y [C]y
Orders of the reaction must be taken in to account when writing a rate equation. Where A, B and C
are reactant, x, y and z are the orders of the reaction with respect to A, B and C.
In my investigation I will vary the concentration of each reactant and I will measure time taken for
the reaction to turn colourless. I will use rate=1/time formula to calculate the rate of the reaction.
This will enable me to draw rate against concentration graph which I will use to ... Show more
content on Helpwriting.net ...
Collision theory:
Reactions only occur when particle of the reactant collide with a certain minimum kinetic energy.
This energy is also known as activation enthalpy this energy must be supplied to the reactant to
enable the bonds to stretch and break and the new bonds to form in the product. Most collisions do
not result in a reaction, only the collision with enough activation enthalpy will react to produce the
product. (1)(2) (10)
Concentration: The collision theory states that for any reaction to take place the two reactant
molecule must collide first. The rate of a reaction depends on the frequency of the collision between
the particles. Increasing the concentration of reactants increases the number of particles available to
react in the same volume of solution. More successful frequent collisions occur in a given time, with
sufficient activation energy to break the chemical bond. Therefore the rate of reaction will increase.
(1)(2)(6)
Surface area: Increasing the surface area of a solid reactant means more particles are exposed to the
other reactant, the number of reaction sites increase therefore it will react more quickly increasing
the reaction time.
Catalyst: A catalyst will increase the rate of reaction by lowering the activation enthalpy without
being chemically unchanged. They do this by providing an alternative pathway, forming an
intermediate compound with the reactant and then it forms the product from

Section 1 Harcourt-Essen Reaction
A2 Chemistry Coursework Section 1 Aims: I aim to find out the order of reaction with respect to
[H2O2] and [2I–]. I aim to find out the activation enthalpy of the reaction by finding the rate of
reaction at different temperatures using the Arrhenius Equation. The experiment will go as follows:
Into a conical flask put 15cm3 of distilled water and add 2cm3 of [X]moldm–3 potassium iodide
(KI) solution and 1cm3 of 2moldm–3 sulphuric acid. Then add to this 2.5cm3 of 5vol (0.42moldm–
3) hydrogen peroxide (H2O2). For the second part of my investigation, the KI solution will remain a
constant 0.3moldm–3 and the H2O2 solution will vary. H2O2 + 2I– + 2H+ –> 2H2O + I2 Methods
to find the rate: 1 – Use a colorimeter to monitor the change ... Show more content on
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Transmittance can be expressed as the ratio of the intensity of the transmitted light (It) and the initial
intensity of the light beam (Io), as expressed by the formula: reference 4 T = It /Io Experimental
Methods: Making up the solutions: The potassium iodide solution will be made up by first
calculating the amount (in moles) of KI needed from the equation: concentration = amount/volume
as I know the desired concentration(s) and how large a volume I want to make up. Then I can
calculate how exactly how much solid KI (in grams) is needed for that concentration by using the
equation: amount = mass/Mr – given the Mr of KI is 166.0028. Then to actually make up the
solution, I will first brush the balance, place a plastic weighing container on it, and then tare the
balance. I will then proceed to accurately weigh out the required mass of KI with a clean spatula.
The hydrogen peroxide solution will be diluted from 20vol to [X]vol by using 20/[X] the volume of
20vol H2O2 in distilled water. Methods: Potassium iodide solution: 1. Using the equations; amount
= mass/Mr and concentration = amount/volume, I calculated the correct mass of KI needed to make
up the required concentrations of KI solution (0.05 through to 0.3moldm–3). I used the complete
values throughout all the equations, and then rounded my final volume to an appropriate decimal
place relative to the precision of the scientific balance I will use to make up the solution. 2. Solid KI
(mass m) was weighed

Chemical Reaction Of Chemical Reactions
Chemical kinetics is the study of rates during chemical processes and the speed at which they occur
(Chm.Davidson, 2016). Chemical kinetics can be altered by the effect of various variables and the
re–arrangement of atoms. An example of kinetic processes can be seen in many experiments such as
the 'Landolt Iodine Clock Reaction.'
Clock reactions represent chemical reactions in which two colourless solutions are mixed together;
at first no reaction takes place but after a short period of time the solution can be seen to undergo a
change in colour. Within the Landolt iodine clock reaction Potassium Iodate and Sodium Bisulphite
react to yield iodine, which in return reacts with the starch molecules to form the blue solution
(RSC, 2016). The process of this experiment can be explained through the following chemical
reactions:
The iodine ions are produced, due to following reaction between iodate and bisulphite:
IO3− + 3 HSO3− → I− + 3 HSO4−
2. The iodate that is left in excess after the first reaction will oxidise with iodide formed to generate
iodine:
IO3− + 5 I− + 6 H+ → 3 I2 + 3 H2O
3. Instantaneously the iodine is reduced back to iodide by the bisulphite I2 + HSO3− + H2O → 2 I−
+ HSO4− + 2 H+
Consequently the iodine will react with the starch to create the coloured solution; this will only
occur once the bisulphite is fully consumed (Unomaha, 2016). Throughout the course of these
chemical reactions, the rate at which the reaction occurs takes place

Chemical Reaction Lab
The objective of this experiment was to allow one to grasp a thorough understanding of chemical
reactions and the way they occur in chemistry. The study of chemical kinetics is known as reaction
rates, which occur at different speeds. The speed of chemical reactions are dependent on four
factors. The main factors that contribute to altering the speed are: the nature of the reactants, the
concentration of the reactants, the presence of a catalysis and lastly, temperature (CHCKY107
General Chemistry Lab Manual Spring 2018). By incrementing the temperature in a chemical
reaction, this incrementation in heat will accelerate the process, creating more collision in particles
as which because they are more motion, creating an increase in kinetic ... Show more content on
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The main factors that contribute to altering the speed are: the nature of the reactants, the
concentration of the reactants, the presence of a catalysis and lastly, temperature (CHCKY107
General Chemistry Lab Manual Spring 2018). By incrementing the temperature in a chemical
reaction, this incrementation in heat will accelerate the process, creating more collision in particles
as which because they are more motion, creating an increase in kinetic energy. Likewise, by
decrementing the temperature, this causes less collision meaning less kinetic energy, resulting in a
more gradual reaction. Similarly, within a reaction, by changing the concentration of the reactants
this changes the number of collisions per unit time (CHCKY107 General Chemistry Lab Manual
Spring 2018). Thirdly, the presence of a catalyst may speed or decrease the reaction by lowering the
activation energy, thus creating an alternate pathway. For the reaction to occur, there must be
sufficient energy reacting with the collision. Lastly, the rate of the reaction is dependent on its nature
since some molecules will react differently to others. Breaking bonds is also an effect which can
vary at different

Factors that Affect the Activity of Urease Essay example
Factors that Affect the Activity of Urease
Aim:
To investigate closely the factors that can affect the activity of urease. The effect of concentration
and temperature can be studied over a period of time leading to the order and activation enthalpy of
the reaction.
Introduction:
UREASE
(NH 2 ) 2 CO + 3H 2 O ––––––––––> 2NH 3 (aq) + CO 2 (g)
Urease is an enzyme found in microorganisms, invertebrates, and higher plants. It catalyses the
hydrolysis of urea to ammonia and carbon dioxide. In some bacteria and invertebrates this reaction
is the final step in the breakdown of complex nitrogenous compounds before ammonia is excreted.
Method:
Quench ... Show more content on Helpwriting.net ...
This combined structure is termed the enzyme–substrate complex. Each type of enzyme will usually
act on only one type of substrate molecule. This is because the shape of the active site will only
allow one shape of molecule to fit in it. The enzyme is said to be specific for this substrate.
There are two types of enzyme inhibitors: Competitive and Non–Competitive inhibition. If an
inhibitor molecule binds only briefly to the active site of the enzyme, there is competition between it
and the substrate for the active site. This means it is more likely that the substrate will collide with a
filled active site and so this is known as competitive inhibition. It is said to be reversible (not
permanent) because it can be reversed by increasing the concentration of the substrate.
Sometimes, the inhibitor can remain permanently bonded with the active site and therefore cause a
permanent block to the substrate. No competition occurs as it does not matter how much substrate is
present. This is non–competitive irreversible inhibition.

Other factors affecting enzyme activity:
Substrate concentration
As substrate concentration increases, the initial rate of reaction also increases as collisions between
enzyme molecules and reactants become more frequent. When the enzymes

The And Characterization Of Project Mn ( Bpmp )
Syntheses and characterization of [Mn(BPMP)(OTf)2] catalysts
BPMP was synthesised via the published procedure [2b] and expected, the piperazine ring adopts
the more stable chair configuration, and the methylpyridyl substituents are found in the equatorial
positions. Reaction of BPMP with Mn(OTf)2 (ratio 1 : 1) in CH3CN under air the atmospheric
conditions this complex [Mn(BPMP)(OTf)2]. Removing of the volatiles and washing with diethyl
ether leads to white solid that analyses as [Mn(BPMP)(OTf)2]. while uncoordinated BPMP was
identified in the ether (washing) phases. The molecular structure is shown in Figure (compare
Scheme 1). The coordination around the manganese atom can be described as distorted trigonal
prismatic, and the piperazine ... Show more content on Helpwriting.net ...
This heterogeneous catalyst can be applied to a wide variety of activated and non–activated primary
and secondary alcohols. As shown in Table 3, benzyl alcohol and substituted benzyl alcohols are
converted to their corresponding aldehydes efficiently. In the case of benzyl alcohol, after 30 min,
only benzaldehyde was obtained in 99% yield. In longer reaction times (1h), the obtained products
are 97% p–OCH3 benzaldehyde and 3% p–OCH3 benzoic acid. The results show that the
substituent's have no major effect on the oxidation of benzylic alcohols. A good selectivity
experimental in the case of cinnamyl alcohol and only oxidized in alcoholic group and no epoxide
yield was obtained. Manganese(II)non–heme was also used for oxidation of secondary alcohols and
their corresponding ketones were obtained in good yields. We used hydrogen peroxide (H2O2) as
the oxidant and [Mn(BPMP)(OTf)2] as the catalyst for the oxidation of alcohols. To a mixture of
substrate (1mmol), manganese non–heme catalyst (1mol %), and solvent (CH3CN = 3mL) was
added H2O2 (1.2mmol). The reaction mixture was stirred for 30 min at room temperature. This
system has shown high catalytic activities for the oxidation of non–activated and activated alcohols
under mild conditions as shown in Table 4. Secondary alcohols were easily converted to the
corresponding ketones in excellent yields and reaction selectivity was over 99% in all cases. Cyclic
alcohols

The Importance Of Chemical Interaction
Kinetics is essentially the study of reaction rates and how they can be affected. Factors such as
concentration, pressure, temperature, and enzyme activity, are commonly tested regarding their
impact on the rate of a reaction (Khan Academy, 2017). It is important to recognise and understand
the components that affect the rate of chemical reactions as this allows control over the reaction
process. Chemical reactions progress naturally at different rates. A chemical reaction involves the
rearrangement of the molecular or ionic structure of substances as they change into other substances
by the breaking of bonds in reactants and the formation of bonds in products (Wilbraham, 2002).
Collision theory can be used to explain why chemical reactions proceed at different rates. Collision
Theory states that atoms, ions and molecules must collide in order for a reaction to proceed and
form products (Stubbings, 2017). Thus, the higher frequency of successful collisions, the faster the
reaction rate will be. Kinetic theory states that particles of matter are in constant motion thus, kinetic
energy is the energy acquired as a result of an object's motion (Wilbraham, 2002). In order for
collisions to be successful however the molecules must acquire a minimum amount of kinetic
energy called their activation energy and they must collide at a precise orientation. The rate of
reaction can be modified with the appropriate knowledge and understandings of the factors affecting
the collisions of

Essay on Lab Report Kinetics of Chemical Reactions
Lab Report Kinetics of Chemical Reactions Kinetics of chemical reactions is how fast a reaction
occurs and determining how the presence of reactants affects reaction rates. In this experiment the
rate of reaction for Fe+3 and I– is determined. Because the rate of chemical reactions relates directly
to concentration of reactants, the rate law is used to find the rate constant, and calculated with
specified temperatures. Two catalyst reactants are used in the experiment, thiosulfate and starch, to
dictate the time of reactions. The order with respect to Fe+3 and I– is also determined by graphing
the slope of the log rate initial as a function of the log (Fe+3) or (I–). The activation energy is also
graphed with the rate constant ... Show more content on Helpwriting.net ...
.004 .0038 2.03 x 10–6 –2.4 –5.69 2. .008 .0078 4.47 x 10–6 –2.1 –5.35 3. .012 .0118 5.68 x 10–6 –
1.9 –5.25 Calculations: [Fe+3] initial: 1. .04 M Fe+3 x 10.00 mL/100.00 mL = .004 [Fe+3] initial 2.
.04 M Fe+3 x 20.00 mL/100.00 mL = .008 [Fe+3] initial 3. .04 M Fe+3 x 30.00 mL/100.00 mL =
.012 [Fe+3] initial [Fe+3] adjusted: 1. .004 [Fe+3] initial –2 x 10–4 = .0038 [Fe+3] adjusted 2. .008
[Fe+3] initial –2 x 10–4 = .0078 [Fe+3] adjusted 3. .012 [Fe+3] initial –2 x 10–4 = .0118 [Fe+3]
adjusted Rate initial = ½ [S2O3–2] initial / time (s) [S2O3–2] initial = .004 m x 10.00 mL / 100.00
mL = .0004 [S2O3–2] initial Rate initial for Combo #1, Combo #2, Combo #3: 1. ½ (.0004) / 98.34s
= 2.03 x 10–6 2. ½

Bioorthogonal Reaction Lab Report
5. Bioorthogonal Click reactions
Click chemistry has wide applications in biotechnology and chemical biology. For use of such
reactions in the above disciplines of science, such click reactions need to be bioorthogonal. A
bioorthogonal reaction is one which takes place without interfering with native biochemical
processes. These type of reactions take place without interfering with components of the living
system. The term bioorthogonal chemistry was coined by scientist Carolyn Bertozzi in 2003
(Wikipedia)
Bioorthogonal click chemistry can be used to visulaize protein expression, track protein localization,
measure protein activity and identify protein interactions within living systems.(Singh et al., 2016)
Types of reactions that fit this definition are as follows
5.1 Condensations of Ketones and Aldehydes with Heteroatom–bound Amines
Historically, the first bio–orthogonal ligations involved ketone–aldehyde condensation reactions.
While ketones and aldehydes can form reversible imine adducts with many amines found in
biological systems, this process is thermodynamically unfavourable in water.
This led to the use of hydrazides and aminooxy reagents, often called 'α–effect amines' because the
heteroatom–bound amine is much more nucleophilic than simple amines and thus shifts the
equilibrium dramatically to the hydrazone and oxime products, respectively. ( book)
Although ketones and aldehydes are absent from the cell surface and from macromolecules within

Introduction
The principles of chemical kinetics is the study of reaction rates and the mechanism in a chemical
reaction.2 The rate of the chemical reaction can be represented as the change in concentration of a
solution with time. Also, the rate reaction can be express in an equation known as the rate law. The
rate law can be express as rate=f([A],[B],[C],...) (1) where the rate reaction is represented as a
function of the concentrations in the chemical equation with time.3 The general chemical reaction
can be shown as aA+bB→cC+dD (2)
Then using Eq. 2, to form the rate of consumption which is the reactant and the rate of formation is
the products
∂[D]/∂t=∂[C]/dt=–∂[A]/dt=–∂[B]/∂t (3) where the rate of reactant or product is instantaneous at a
given time.
The rate of the reaction can also be written using Eq. 1 as rate=k[A]^x [B]^y (4) where the
concentration are raised to a power are proportional and k is called the rate constant. The rate
constant is independent of the concentration but depend on the temperature.2 The exponents are
called the order of the reaction and the different type of order of reaction are determine by the sum
of the exponents.3 The first order rate law is shown as rate=k[A]^1=–∂[A]/∂t (5) using Eq. 3 an Eq.
4 and rearranging Eq. 5 to form
–∂[A]/[A] =k∂t (6)
Then integrating Eq. 6 at the initial time (t=0) for concentration of A to be [A]0 and [A]t at a later
time to form the limit of the integration for the first–order

Chemical Kinetics: Enzymes Essay
Chemical Kinetics is the branch of chemistry that studies the speed at which a chemical reaction
occur and the factor that influence this speed. What is meant by the speed of a reaction is the rate at
which the concentrations of reactants and products change within a time period. Some reactions
occur almost instantaneously, while others take days or years. Chemical kinetics understanding I
used in the process of designing drugs, controlling pollution and the processing of food. Most of the
time chemical kinetics is used to speed or to increase the rate of a reaction rather than to maximize
the amount of product. The rate of a reaction is often expressed in terms of change in concentration
(Δ [ ]) per unit of time (Δ t). We can measure the ... Show more content on Helpwriting.net ...
An interesting result is obtained when the instantaneous rate of reaction is calculated at various
points along the curve in the graph of the change in concentration versus time. The rate of reaction
at every point on this curve is directly proportional to the concentration of the reactants at that
moment of time.
Rate = k(reactant concentration)
Because this equation is an experimental law that describes the rate of the reaction, it is called the
rate law for the reaction. The proportionality constant, k, is known as the rate constant. For general
reactions (aA + bB cC + dD) the rate law is (rate = k[A]x[B]y) where k is the rate constant and the
exponents x and y are numbers that must be establish experimentally. The values of the exponents in
the rate law indicate the order of the reaction with respect to each reactant. The sum of x and y is
called the overall reaction order.
Catalysts are one of the factors that extremely affect the rate of a reaction. Catalysts are substances
that speed up the rate of a reaction without being consumed themselves. When the reaction has
ended, you would have exactly the same mass of catalyst as you had at the beginning. One common
example are enzymes which are catalysts used to speed chemical reactions inside our body.
Enzymes bind for the time being to one or more of the reactants, substrate(s), of the reaction they

Chemical Reaction Kinetics
Reaction Kinetics
Kinetics of reactions, otherwise known as chemical kinetics, is the study of how particles and bonds
between particles change in a chemical reaction over time. These changes can be viewed at a
molecular level through the use of reaction rates. Reactions rates tell us how fast or how slow the
change is happening at this level, or how the reaction depends on the time.
In Chapter 14 of the textbook, it was given that a chemical reaction only occurs if there is a collision
between particles. The greater the amount of particles, then the greater the amoutn of collisions in a
given amount of time, the faster the rate of the chemical reation. So the rate of a reaction depends on
the concentration of the particles in the reation. ... Show more content on Helpwriting.net ...
If a chemical reaction has a slow rate, a relatively small fraction of molecules reacts to form
products in a given period of time." (Chemistry, 557) This can be applied to the rate reactions for
chemicals. How much of the reactants are used in a certain amount of time to produce the products,
is called the rate of the reaction. When finding the reaction rate of a chemical reaction, many factors
need to be included. First, we need to know what we are looking for. In Chemistry Structures and
Properties, the author provides examples such as the speed of a car being expressed in miles per
hour, or weight lost in lbs per week. We would have speed and weight, respectively, as units for our
answers. In the reaction A2 + B2 –> 2AB, for every 1 mol of A2 and B2 used, 2 mols of AB are
produced. In a chemical reaction the reactants are used up in order to form the products. In this case
the A2 and B2 are the reactants and AB is the product.
In order to find the numerical rate of a reaction, more than just the balanced equation is needed. In
the gas example above, the rate at which the gas will be consumed, and the distance, or miles, is
needed in order to find how much will be needed. This is where rate laws come into effect. Rate
laws use the balanced equation to express the relationship between the reations rate and the
reactions concentration. (Chemistry,

Review 3: Text Chemical kinetics is the study of rates and mechanisms of chemical reactions. In our
study of chemical kinetics, experimental data identifying the initial concentrations of reactants and
the instantaneous initial rates of multiple trials is used to determine the rate law for the reaction, the
order of the reactants, the overall reaction order, and the average rate constant. By comparing the
instantaneous initial rates and the initial concentrations of the reactants for two trials, it is possible to
deduce the order of each reactant. In order to determine the order of A, the two trials must be
selected such that the concentration of A changes while the concentration of B is held constant. In
this case, trial 1 and trial 3 or trial 2 and ... Show more content on Helpwriting.net ...
k=(0.103M–2s–1+0.103M–2s–1+0.103M–2s–1+0.103M–2s–1)/4=0.103 M–2s–1 The average rate
constant is 0.103M–2s–1. Combining everything, the rate law for the reaction is Rate=(0.103M–2s–
1)[A]2[B]1. We know that the reaction is 2A+2B→C+D. Based on the orders we calculated for A
and B, we know that this reaction is not an elementary reaction because both of the coefficients of A
and B are 2, which do not match the calculated orders of A and B, which are 2 and 1 respectively.
Also, if this were an elementary reaction, we would expect 3 molecules to perfectly collide with
each other, which is highly unlikely. As a result, it is more likely that there was an intermediate and
that multiple steps were involved. Through experimental data, we can not only determine the order
of reactants, but also the rate law, the average rate constant, and the overall order of the reaction.
Using the orders calculated, we can also determine the integrated rate plot that best represents the
reactants and the type of

Lab Repor Chemical Kinetics Essay
Abstract The "Chemical Kinetics" experiment was done to investigate the changes in the rate of
reaction under the effect of concentration, temperature, and presence of a catalyst. It was determined
that as the concentration of reactants and the temperature increases, the rate of the reaction increases
as well. Also, the reaction was run by the presence of catalyst, and the rate of the reaction increased
drastically in the presence of it. The order of the reaction with respect to each reactant was
calculated to be: x = 1 [I–], y = 1 [BrO3–], z = 2 [H+] by the method of initial rates. The average
rate constant was determined to be 26.7 M–3s–1, and the activation energy was calculated to be 49.6
kJ/mol. Introduction The whole purpose ... Show more content on Helpwriting.net ...
The reaction occurred under three different temperatures: 40ْ C, 10ْ C, and 0ْ C. The experiment in
this part was carried out just like part one. In flask 1, 10 mL of 0.010 M KI, 10 mL of 0.0010 M
Na2S2O3, and 10 mL of H2O were mixed. In flask 2, 10 mL of 0.040 M KBrO3 and 10 mL of 0.10
M HCl were mixed, and 3 drops of starch was added. Then, the two flasks were put in an ice bath
and cooled to about 10ْ C. Afterwards, the two solutions were mixed together while in the ice bath
with swirling until turning blue. The time was recorded. The reaction was done the same way for the
other two degrees (0ْ C, 10ْ C). If the water needed to be cold, ice was added, and if hot water was
needed, the water was heated. In the third part of the experiment, the reaction was carried out in the
presence of a catalyst. The influence of the catalyst on the rate of the reaction was investigated.
Again, mixture 1 from part one was used. In flask 1, 10 mL of 0.010 M KI, 10 mL of 0.0010 M
Na2S2O3 ,and 10 mL of H2O were mixed. In flask 2, 10 mL of 0.040 M KBrO3 and 10 mL of 0.10
M HCl were mixed, and 3 drops of starch were added. Also, one drop of 0.5 M (NH4)2MoO4,
ammonium molybdate, was added to Flask 2 which acted as a catalyst. The two solutions were
mixed until a blue color was formed and the stopwatch was stopped. All the

A Chemical Reaction By Light
Photocatalysis is the acceleration of a chemical reaction by light. The activity of these catalysts
usually depends on their ability to produce pairs of negatively charged electrons and positively
charged electron holes (electron–hole pairs) on material surfaces, which is induced by light
irradiation. An electron hole is the absence of an electron from the full valence band. Furthermore,
as light interacts with matter in the form of energy packets, the photons, it excites an electron
consequently causing it to move to a higher energy orbital leaving a vacancy, a hole, in its previous
position (ground state orbital). The creation of these electron–hole pairs brings about various
chemical processes, such as the formation of free radicals. Free radicals are highly reactive chemical
species, which may then go on to give secondary reactions.
It is well documented that light energized, photocatalytic TiO2 is a safe, non–toxic, anti– oxidant
that produces hydroxyl radicals (OH–) that are remarkably effective in rapidly decomposing organic
compounds. When UV light is emitted on the titanium dioxide, electron are released. The electrons
interact with water molecules (H2O) in the solution, breaking them up into hydroxyl radicals (OH·),
which are highly reactive, short–lived, uncharged forms of hydroxide ions (OH−). These agile
hydroxyl radicals attack the organic (carbon–based) molecules from which most dirt and other
harmful chemicals are made of, breaking apart their chemical

Discussion chemical Equilibria and kinetics
Discussion Our experiment is divided into 9 parts:
A. Effect of Nature of Reactants to the reaction rate.
B. Effect of Temperature to the reaction
C. Effect of Concentration to the Reaction Rate
D. Effect of Catalyst to the Reaction Rate
E. Chromate–Dichromate Equilibrium
F. Thiocyanatoiron (III) Complex Ion Equilibrium
G. Weak Acid Equilibrium (Ionization of Acetic Acid)
H. Weak Base Equilibrium Ionization of Ammonia
I. Saturated Salt (Sodium Chloride) Equilibrium
On part (A) we are to observe which reaction rate is faster, and doing the experiment. We have
concluded that:
"Aluminum had faster rate of reaction rate than iron because it is more active than iron based on the
activity series."
TABLE B.
Temperature (C)
Time ... Show more content on Helpwriting.net ...
This diagram, at right, shows a graph (purple line) of chemical potential energy (vertical axis) versus
a "reaction coordinate" (horizontal axis), which here represents the progress of a reaction in which
one bond must break and a new bond forms. Examples of such reactions are provided by the many
isomerization reactions, such as the interconversion of cis–2–butene and trans–2–butene.
Let us first consider the forward reaction, A → B. Reactant molecules (A) in the system with enough
energy to reach the energetic peak, the transition state(symbolized by the double dagger, ‡) can
continue forward along the reaction coordinate to conversion to product B.
This minimum energy required is the activation energy. For the forward reaction, this is symbolized
as Ea, fwd, and is the energetic cost required to advance the bond breaking in a molecule of A to the
point where formation of the new bond in B can begin to provide an energetic payback. The increase
in potential energy must be provided by the kinetic energy of the molecules in the system, which
varies by temperature, according to a Maxwell–Boltzmann distribution. For molecules, the kinetic
energy can reside not only in their motion through space, but also in bond stretching, bending, and
twisting. Kinetic energy in these forms is constantly being redistributed by

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