Calculations Involving a Limiting Reactant

Question 16.

This question has multiple parts. Work all the parts toget the most points.

a. \"Smelling salts,\" which are used to revive someone who hasfainted, typically contain ammonium carbonate,(NH₄)₂CO₃. Ammonium carbonatedecomposes readily to form ammonia, carbon dioxide, and water. Thestrong odor of the ammonia usually restores consciousness in theperson who has fainted. The unbalanced equation is

(NH₄)₂CO₃(s) →NH₃(g) + CO₂(g) + H₂O(g)

Calculate the mass of ammonia gas that is produced if 2.25 g ofammonium carbonate decomposes completely.

___________________ g NH3

b. Sulfurous acid is unstable in aqueous solution and graduallydecomposes to water and sulfur dioxide gas (which explains thechoking odor associated with sulfurous acid solutions).

H₂SO₃(aq) → H₂O(l) +SO₂(g)

If 6.50 g of sulfurous acid undergoes this reaction, what massof sulfur dioxide is released?

_____________________ g SO2

c. For the following unbalanced chemical equation, suppose thatexactly 1.75 g of each reactant is taken. Determine which reactantis limiting, and calculate what mass of CO₂ is expected(assuming that the limiting reactant is completely consumed).

CS₂(l) + O₂(g) → CO₂(g) +SO₂(g)

Limiting reactant is _______________________

__________________ g CO2

d.   Lead(II) carbonate, also called \"white lead,\" wasformerly used as a pigment in white paints. However, because of itstoxicity, lead can no longer be used in paints intended forresidential homes. Lead(II) carbonate is prepared industrially byreaction of aqueous lead(II) acetate with carbon dioxide gas. Theunbalanced equation is

Pb(C₂H₃O₂)₂(aq) +H₂O(l) + CO₂(g) →

PbCO₃(s) +2HC₂H₃O₂(aq)

Suppose an aqueous solution containing 1.35 g of lead(II)acetate is treated with 5.95 g of carbon dioxide. Calculate thetheoretical yield of lead carbonate.

_______________________ g PbCO3