Name: _____________________________
Period: ______
Date: ______________________
2C.7 Supplement: Molar Relationships-II
When the molar masses and molar relationships between reactants and products are known,
chemists can calculate the amounts of material they need or will produce using a particular
reaction.
1. On a small scale, calcium can be isolated through the reaction of calcium chloride with
sodium metal, as shown in the following equation:
CaCl2 + 2Na → Ca + 2NaCl
a. How many moles of Na are needed to react with 7.00 mol CaCl2?
b. How many moles of NaCl are produced by the reaction of 14.0 mol Na?
c. How many moles of Ca are produced from 3.5 mol Na?
2. Magnetite, an iron ore, can be reduced to form metallic iron by a process called
pyrometallurgy. One reaction that occurs during this process is:
Fe3O4 + 4CO → 3Fe + 4CO2
a. How many moles of CO are needed to react with 3.5 mol Fe3O4?
b. How many moles of CO2 are produced by the reaction of 7.00? mol CO? Assume adequate
amount of Fe3O4.
c. How many mol of Fe are produced from 5.0 mol CO? Assume adequate amount of Fe3O4.
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Name: _____________________________
Period: ______
Date: ______________________
2C.7 Supplement: Molar Relationships-II (Page 2)
3. For the reaction in Question 2: Fe3O4 + 4CO → 3Fe + 4CO2
a. What mass of Fe can be produced from the complete reaction of 4.0 mol CO? Assume
adequate amount of Fe3O4.
b. What mass of CO2 can be produced from 25.0 g Fe3O4? Assume that there is excess CO
available for reaction.
c. What mass of CO, which fully reacts, will produce 210.0 g Fe?
4. Tungsten can be prepared from one of its minerals as illustrated in the following equation:
WO3 + 3H2 → W + 3H2O
a. What mass of H2O can be produced from the complete reaction of 100.0 g WO3, given an
excess of hydrogen?
b. What mass of H2 is needed to produce 75.0 g W?
c. What mass of W can be produced from the complete reaction of 25.0 g WO3, assuming
excess H2?
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