Stoichiometry Review

Use the balanced equation and the Molar Mass table above to answer the following question.

How many grams Ca₃(PO₄)_2(s) could be produced in an industrial process if 55.00 g of CaCl₂ in solution reacted completely with sufficient Na₃(PO₄)_(aq)?

• 310.2 g

• 155.1 g

• 103.4 g

• 51.70 g

In the reaction 2RbNO₃ → 2RbNO₂ + O₂, how many moles of O₂ are produced when 5.0 mol of RbNO₃ decompose?

• 1.0 mol

• 2.5 mol

• 3.0 mol

• 7.5 mol

In 1860, Robert Boyle was the first to use phosphorus to ignite sulfur-tipped wooden splints that gave rise to our modern matches. One of the ways it can be made involves the chemical reaction of calcium phosphate with carbon and silicon dioxide in a furnace:

2Ca₃ (PO₄ )₂ + 6SiO₂ + 10C → 6CaSiO₃ + P₄ + 10CO

Refer to the information above. If you use 100.0 grams of calcium phosphate and an excess of silicon dioxide and carbon, how many moles of phosphorus will be produced?

• .1612 moles

• .3224 moles

• 15510 moles

• 1.551 moles

In the reaction N₂ + 3H₂ → 2NH₃, what is the mole ratio of hydrogen to nitrogen?

• 1 : 1

• 1 : 2

• 3 : 1

• 3 : 2