дано
m(C3H8) = 22 g
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V(O2)-?
V(возд)-?
C3H8+5O2-->3CO2+4H2O
M(C3H8) = 44 g/mol
n(C3H8) = m/M = 22 / 44 = 0.5 mol
n(C3H8) = 5n(O2)
n(O2) = 5* 0.5 = 2.5 mol
V(O2) = n*Vm = 2.5 * 22.4 = 56 L
V(возд) = V(O2) * 100% / 21% = 56 * 100% / 21% = 266.7 L
ответ 56 л, 266.7 л