Percent Yield Exercises

1.	Lead(II) sulfide, PbS, reacts with oxygen gas to produce lead(II) oxide and sulfur dioxide. If 0.500 moles of O₂ were consumed using this chemical reaction, how many grams of lead(II) oxide would be produced? (Ar: O=16; Pb=207; S=32) Ans: 74.3
	2 PbS + 3 O₂ 2 PbO + 2 SO₂
2.	Potassium chlorate, KClO₃, decomposes when heated to produce potassium chloride and oxygen gas. If 2.50 grams of KClO₃ were heated in a test tube, how many grams of oxygen gas should be given off? (Ar: O=16; Cl=35.5; K=39) Ans: 0.980 g
	2 KClO₃ 2 KCl + 3 O₂

3.	The reaction between 15.8 g of NH₃ and excess oxygen gas produces 21.8 g of NO gas and some water. Determine the percent yield. (Ar: O=16; N=14; H=1) Ans: 78.19
	4 NH₃+ 5 O₂4 NO + 6 H₂O
4.	For the balanced equation shown below, if the reaction of 77.0 grams of CaCN₂ produces 27.1 grams of NH₃, what is the percent yield? (Ar: O=16; N=14; H=1; Ca=40; C=12) Ans: 82.8
	CaCN₂+ 3 H₂O CaCO₃+ 2 NH₃
5.	For the balanced equation shown below, if the reaction of 91.3 grams of C₃H₆ produces at 81.3% yield, how many grams of CO₂ would be produced? (Ar: O=16; H=1; C=12) Ans: 233
	2 C₃H₆+ 9 O₂6 CO₂+ 6 H₂O
6.	For the balanced equation shown below, if the reaction of 20.7 grams of CaCO₃ produces 6.81 grams of CaO, what is the percent yield?(Ar: O=16; Ca=40; C=12) Ans: 58.75
	CaCO₃CaO + CO₂
7.	Given the following equation and you start with 389.4 g of Al2(SO3)3 and you isolate 212.4 g of Na2SO3, what is your percent yield for this reaction? (Ar: O=16; Al=27; Na=23; S=32; H=1) Ans: 42.42% Al₂(SO₃)₃ + 6 NaOH 3Na₂SO₃ + 2 Al(OH)₃

PERCENT YIELD EXERCISES