Chemical formulas are present in this PPT file. Some of the basic chemical formulas you can learn and write from here. These are not tough neither too complex.

2. • Recognize that chemical formulas are used to identify
substances and determine the number of atoms of each
element in chemical formulas containing subscripts.
• Recognize whether a chemical equation containing
coefficients is balanced or not and how that relates to
the law of conservation of mass.
• Recognize the importance of formulas and equations in
representing chemical reactions– 1998 TEKS 8.9C

3. • Teacher can type answers in here.

5. • Chemical, or molecular, formulas are a concise way of
expressing information about the atoms that constitute a
particular chemical compound.
• Wait…what?
• It is an expression which states the number and type of
atoms present in a molecule of a substance.

10. MgSO
4

13. • A subscript is used to represent the number of each atom
being represented.
• They are only used when more than one atom is being
represented. If only one atom is represented, there is no
subscript.
• In the formula for water, what is the subscript?
• There is only one atom of Oxygen, so it does not have a
subscript.
H2O
H2O H = Hydrogen
O = Oxygen

14. • Usually the subscript just multiplies or shows the number of
atoms of a single element. If the subscript exists outside of a
set of parenthesis then it will multiply the atoms of all of the
elements inside the parenthesis.
• How many of each atom are there now?
• Answer: Nitrogen-1, Carbon-3, Hydrogen-9
N(CH3)
N = Nitrogen
C = Carbon
H = Hydrogen

16. • In this image Hydrogen atoms are white and Nitrogen
atom is red.
• Write the chemical formula for this molecule.
Answer: NH3
This substance
is ammonia

17. • In this image the Carbon atom is black and the Oxygen
atoms are red.
• Write the chemical formula for this molecule.
Answer: CO3
This substance is carbonate

18. • In this image blue represents Nitrogen atoms, red
represents Oxygen atoms, white represents Hydrogen
atoms and black represents Carbon atoms.
• Write the chemical formula for this molecule.
Answer: C8H10N4O2
This substance is caffeine

19. • In this image the Carbon atom is blue and
the Oxygen atom is red.
• Write the chemical formula for this
molecule.
Answer: CO
This substance is carbon monoxide

20. • A harder one:
In this image Nitrogen atoms are blue, the
Platinum atom is grey, Chlorine atoms are
green, and Hydrogen atoms are white.
• Write the chemical formula for this molecule.
Answer: N2PtH6Cl2

22. 7H2
• Coefficients appear on the left side of a chemical formula.
• They are used to multiply all the atoms in a compound
• In the following formula, which is the coefficient?
• Earlier we learned that the subscript 2 meant that there
were two Hydrogen atoms. The coefficient 7 means there
are 7 times more.
• How many Hydrogen atoms do we have?
• How many Oxygen atoms?
7H2

24. • representation of chemical reaction in equation: a
representation, using chemical symbols in a form
resembling a mathematical equation, of the process
involved in a chemical reaction
• This is an example of a chemical equation. The
components on the left combine together to yield
(represented by the arrow) the component on the right.
2H2+O22H2O

26. • The quantity of a specified product obtained in a reaction
or series of reactions, usually expressed as a percentage
of the quantity that is theoretically obtainable

28. • What is produced.
• Which side represents the products?
• They are found on the right side of a chemical equation.
2H2+O22H2O
2H2+O22H2O

30. • The starting substances.
• Which side represents the reactants?
• They are found on the left side of a chemical equation.
2H2+O22H2O
2H2+O22H2O

32. • Atoms are neither created, nor destroyed, during any
chemical reaction.
• This means that the same number of atoms that are
present after a reaction are the same number of atoms
that are present before a reaction.
• There is only a rearrangement

35. • Write out your “un-balanced” equation using formulas of
reactants and products.
CH4+O2CO2+H2O

36. • Count up the atoms in the products and reactants.
• How many carbons, hydrogens, and oxygens are on
each side? Are they equal?
CH4+O2CO2+H2O
C=1
H=4
O=2
C=1
H=2
O=3
They are
NOT equal

37. • Since our carbons are ok we will not mess with those
now.
• However, we have half the number of hydrogens in the
products than we do in the reactants.
• What do we need to add? Where do we add it?
CH4+O2CO2+H2O
CH4+O2CO2+2H2
O C=1
H=4
O=2
C=1
H=4
O=4
They are
still NOT
equal

38. • Now we have half the number of Oxygens.
• What do we need to add? Where do we need to add it?
Is everything equal now?
CH4+O2CO2+2H2O
CH4+2O2CO2+2H2O
C=1
H=4
O=4
C=1
H=4
O=4
They ARE
now
balanced

40. H2+O2H2
O
2H2+O22H2O

41. Fe+Cl2FeCl3
2Fe+3Cl22FeC
l3

42. Cu+AgNO3Cu(NO3)2+A
g
Cu+2AgNO3Cu(NO3)2+2Ag

43. Zn+HClZnCl2+
H2
Zn+2HClZnCl2+H
2

44. Pb(NO3)2+AlCl3PbCl2+Al(NO
3)3
3Pb(NO3)2+2AlCl33PbCl2+2Al(NO3
)3