Question #dc3c2

1 Answer
May 6, 2016

First write the balanced oxidation-reduction reaction, then determine the number of moles of iron, then moles of H_2, then calculate the volume of gas using the ideal gas law , and finally multiply by 0.75 for the yield. (whew!)

Explanation:

Fe + 2 H^+ -> Fe^(2+) + H_2

(11.2 g)/(55.845 g/(mol)) = 0.201 mol Fe = 0.201 mol H_2

STP = standard temperature and pressure:
1 atm pressure and 273.15 K

Using the ideal gas law, where R = 0.08206 L-atm/(mol-K):

V = (nRT)/P = (0.201*0.08206*273)/1 = 4.50 L

75% yield gives V = 4.50 L times 0.75 = 3.38 L