• Stoichiometry is the science of measuring the quantitative proportions or mass ratios in which chemical elements stand to one another.

• BASICALLY…IT IS THE STUDY OF THE RELATIONSHIP BETWEEN THE MASSES (SOMETIMES VOLUMES).

2 +

How many pieces of bread are required to make a sandwich with 14 pieces of ham? (1 slice of ham per sandwich)

MOLE TO MOLE

MOLE TO MASS

MASS TO MOLE

MASS TO MASS

•Question?–How many moles of lithium hydroxide are required to react with 20 moles of CO2?•CO2(g) + LiOH(s) Li2CO3(s) +

H2O(l)

• √ for a balance equation

–CO2(g) + LiOH(s) Li2CO3(s) + H2O(l)

• 1 C 1 C 3 O 4 O 1 Li 2 Li 1 H 2 H

• If not, balance it!– CO2(g) + 2 LiOH(s) Li2CO3(s) +

H2O(l)

• 1 C 1 C 4 33 O 4 O 2 11 Li 2 Li 2 1 H 2 H

• Find mole ratio

• CO2(g) + 2 LiOH(s) Li2CO3(s) + H2O(l)

– mol LiOH mol CO2

•Use the coefficients as the mole ratio• 2 mol LiOH 1 mol CO2

• Convert moles given to moles wanted– Give 20 moles of CO2

• 20 mol CO22 mol LiOH

1 mol CO2

= 40 mol LiOH

• Question?– What is the mass of carbon dioxide, in grams,

is needed to react with 3.00 mol of H2O in the photosynthesis reaction?

• 6CO2 + 6 H2O C6H12O6 + 6 O2

• √ for a balance equation

–6CO2 + 6 H2O C6H12O6 + 6 O2

• Find mole ratio

• 6CO2 + 6 H2O C6H12O6 + 6 O2

– mol CO2

mol H2O

•Use the coefficients as the mole ratio• 6 mol CO2

6 mol H2O

• Convert moles given to moles wanted– Given 20 moles of CO2

• 3 mol H2O 6 mol CO2

6 mol H2O

= 3 mol CO2

• Convert the moles to grams.– 3.00 mol CO2 44.01g CO2

mol CO2

= 132 g CO2

• Question?– The following reaction is run using 824 g of

NH3, how many moles of NO are formed?

• NH3 + O2 NO + H2O

• √ for a balance equation

–NH3 + O2 NO + H2O

• It’s not, so balance it!

– 4NH3 +5O2 4 NO + 6H2O

• Given grams convert to moles– 824 g NH3 1mol NH3

17.04 g NH3

= 48.4 mol NH3

• Find mole ratio

• 4NH3 +5O2 4 NO + 6H2O– mol NO mol NH3

•Use the coefficients as the mole ratio• 4 mol NO 4 mol NH3

• Convert moles to moles wanted

– 48.4 mol NH3 4 mol NO

4mol NH3

= 48.4 mol NO

• Do everything like the last problem BUT add ONE STEP!!!

– Question?

• How many grams of NO are formed?

• Take the 48.4 mol NO and convert it to grams.– 48.4 mol NO 30.01g NO

1 mol NO

= 1452.48g NO