1. For the balanced equation shown below, if the reaction of 40.8 grams of C6H6O3 produces a 39.0% yield, how many grams of H2O would be produced ?
C6H6O3+6O2=>6CO2+3H2O
C = 12
H = 1
O = 16
12 * 6 = 72
1 * 6 = 6
16 * 3 = 48
48 + 6 + 72 = 126 grams/mole
1 * 2 = 2
16 * 1 = 16
2 + 16 = 18 grams/mole
126 * 1 = 126
18 * 3 = 54
54/126 = .428
.428 * 40.8 = 17.5 = theoretical yield
39 = (actual yield/ 17.5) * 100
39 = (actual yield/ 17.5) * 100
100
17.5 * .39 = actual yield/17.5 * 17.5
actual yield = 6.83 grams
2. 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?
CaCO3=>CaO+CO2
Ca = 40
C = 12
O = 16
40 * 1 = 40
12 * 1 = 12
16 * 3 = 48
40 + 12 + 48 = 100 grams/mole
40 * 1 = 40
16 * 1 = 16
40 +16 = 56 grams/mole
56/100 = .56
.56 * 20.7 = 11.6
theoretical yield = 11.6 grams
percentage yield = (6.81/11.6) * 100 = 58.7%
3. For the balanced equation shown below, if the reaction of 91.3 grams of C3H6 produces a 81.3% yield, how many grams of CO2 would be produced?
2C3H6+9O2=>6CO2+6H2O
C = 12
H = 1
O = 16
12 * 3 = 36
1 * 6 = 6
36 + 6 = 42 grams/mole
12 * 1 = 12
16 * 2 = 32
12 + 32 = 44
42 * 2 = 84 44 * 6 = 264
264/84 = 3.14
3.14 * 91.3 = 286
81.3 = (actual yield/ 286) * 100
81.3 = (actual yield/ 286) * 100
100
286 * .831 = actual yield
actual yield = 232 grams
4. For the balanced equation shown below, if the reaction of 0.112 grams of H2 produces 0.745 grams of H2O, what is the percent yield?
Fe3O4+4H2=>3Fe+4H2O
H = 1
O = 16
1 * 2 = 2 grams/mole
1 * 2 = 2
16 * 1 = 16
2 + 16 = 18 grams/mole
2 * 4 = 8 18 * 4 = 72
72/8 = 9
9 * .112 = 1
percentage yield = (.745/1) * 100 = 74.5 %
percentage yield = 74.5%
5. 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?
CaCN2+3H2O=>CaCO3+2NH3
Ca = 40
C = 12
N = 14
H = 1
40 * 1 = 40
12 * 1 = 12
14 * 2 = 28
40 + 12 + 28 = 80 grams/mole
14 * 1 = 14
1 * 3 = 3
14 + 3 = 17 grams/mole
80 * 1 = 80 17 * 2 = 34
34/80 = .425
.425 * 77 = 32.7
percentage yield = (27/32.7) * 100
percentage yield = (.83) * 100
percentage yield = 83 %