n(niu)= m/M= 4000g/2g/mol= 2000mol H2
pV= nRT
2XV= 2000x0,082x(27+273)
V=24600 L
1mol.....0,5mol
H2 + 1/2O2----> H2O
2000......x
x= 1000molO2
V.O2= nxVm= 1000molx22,4 l/mol= 22400 l
100l aer..........20l O2
x.......................22400 l
Vaer= 5x22400 l=...................calculez
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