Дано
m(ppa H2SO4)=98 g
W=20 %
m(Zn)=6.5 g
------------------------------
V(H2)-?
находим массу вещества
m(H2SO4)=98*20%/100%=19.6 g
19.6 6.5 Xg
H2SO4+Zn-->ZnSO4+H2
65 22.4
M(H2SO4)=98 g/mol
M(Zn)=65 g/mol
M(ZnSO4)=161 g/mol
Vm=22.4L/mol
n(H2SO4)=19.6/98=0.2 mol
n(Zn)=6.5/65=0.1 mol
n(H2SO4)>n(Zn)
6.5/65 = X/22.4
X=2.24 L
ответ 2.24 л