2. 5.2 Stoichiometry

3. Moles 6.022×1023 Particles 1mol = 22.4L @ STP 1mol = Molar Mass
The mass of 1 mole of a substance in grams (also known as Gram Atomic Mass)
Mass given on periodic table is in amu
Because amu and grams are relative we can say the masses on the periodic table are in grams

4. Molar Conversions in a Reaction
The coefficients in a balanced equation indicate the number of particles of each substance or the relationship of particles to each other.
N2H4 + 2H2O2 → N2 + 4H2O
1 mol N2H4 = 2 mol H2O2 =
1 mol N2 = 4 mol H2O

5. Sample Problems
How many liters of oxygen are necessary for the combustion of 340. g of ethanol (C2H5OH)?
The balanced equation is:
C2H5OH + 3O2 → 2CO2 + 3H2O
496 L O2

6. Sample Problem
What volume of hydrogen gas, along with nitrogen gas, is necessary to produce 16.0 L of ammonia gas (NH3)?
24.0 L H2

7. Sample Problem
How many moles of bromine (Br2) are produced when fluorine reacts with g of potassium bromide?
1.46 mol Br2

8. Sample Problem
In a thermite reaction, powdered aluminum reacts with iron(III) oxide to produce aluminum oxide and molten iron. What mass of aluminum oxide is produced when 2.3 g of aluminum reacts with iron(III) oxide?
4.3 g Al2O3