将2.3克金属钠与2.7克铝条先后投入盛有50ml水的烧杯之中，在标准情况下生成氢气多少升？若要使溶液中的铝元素全部转化

2Na+2H2O=2NaOH+H2
46.............2
2.3g...........x
46/2.3=2/x
x=0.1g
2Al+2NaOH+H2O=NaAlO2+3H2
54..............82.....6
2.7..............z....y
54/2.7=6/y
y=0.3g
v(H2)=(0.1+0.3)/2 x22.4=4.48L
54/2.7=82/z
z=4.1g
NaAlO2+H2O+HCl=NaCl+Al(OH)3
82..........36.5
4.1g.........a
82/4.1=36.5/a
a=1.825g
n(HCl)=1.825/36.5=0.05mol
v=0.05/2=0.025L=25mL