DE CHEMISTRY – King William High School
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1 mole = 6.02 x 1023 particles
EX: How many molecules of CO2 are in 1.75
moles?
EX: How many moles of carbon are in 1.50
moles of C5H10O2?
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The amount of grams equal to one mole
(decimal # from periodic table)
EX: What is the molar mass of aluminum
oxide?
How many grams are in 0.500 moles of
sodium chloride?
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Left of the arrow = reactants (what you start
with)
Right of the arrow = products (what you end
up with…what you make)
Must be balanced because of the Law of
Conservation of Mass
EX: Fe2S3 + HCL  FeCl3 + H2S
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EX: Na3PO4 + MgCl2  Mg3(PO4)2 + NaCl
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Synthesis (or combination)  one product
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Decomposition  one reactant
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Single replacement  one element + one
compound on each side of the arrow
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Double replacement  2 compounds on each
side of the arrow
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Combustion  oxygen is a reactant
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Electrons are transferred from one substance
to another
OIL RIG
EX: Cu (s) + O2 (g)  CuO (s)
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How many moles of sulfur are needed to
react with 1.42 moles of iron?
Fe (s) + S (s)  Fe2S3 (s)
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How many grams of carbon dioxide are
produced when 54.6 g of acetylene is burned?
C2H2 + O2  CO2 + H2O
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Exothermic – released of energy (energy is a
product and DH is negative)
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Endothermic – energy is absorbed (energy is
a reactant and DH is positive)
How can you speed the rate of a reaction up???
 Temperature (molecules move faster so there
is a better chance that they collide and react)
 Concentration (more collisions because more
molecules in a given space)
 Catalyst (lowers energy of activation)