A,Na=23g/mol; Vm(volumul molar)=22,4 l/mol
n(niu)= m/M= 92g/23g/mol=4mol Na
calculez moli si volum H2 din ecuatia
2mol.......................................1mol
2Na+ 2H2O---> 2NaOH + H2
4mol......................................x=n=2mol
V=nxVm= 2molx22,4l/mol= .....................calculeaza !!!!!