given the reaction -

Question

Fe(s)+H2SO4(aq)->FeSO4(aq) + H2(g)
the volume of the balloon was 4400m^3 and the loss of hydrogen gas during filling was est. at 20%. what mass of iron splints and 87% (by mass) H2SO4 were needed to ensure complete filling of the balloon? assume temp of 0C pressure of 1.0atm and 100% yeild.

Answer 1

I would first divide 4400 m^3 by 0.80 (only 80% efficient in filling). Then
use PV = nRT to calculate n, the mols of H2 required to fill the balloon. P is in atm, V in liters (use the value above which you calculated but change to liters), R is 0.08205, T is in Kelvin.

Convert mols H2 gas needed to mols Fe(s) and mols H2SO4.
Convert mols Fe to grams Fe.
Convert mols H2SO4 to grams H2SO4, then divide that by 0.87 (since it's only 87% by mass good stuff).
Check my thinking.