(1)
Al2(SO4)3~2Al(OH)3
342g 156g
1.71g m[Al(OH)3]
m[Al(OH)3]=0.78g
HCl NaOH
1mol 1mol
0.01mol n1(NaOH)
n1(NaOH)=0.01mol
Al2(SO4)3~8NaOH
342g 8mol
1.71g n2(NaOH)
n2(NaOH)=0.04mol
n(NaOH)=n1(NaOH)+n2(NaOH)=0.05mol
c(NaOH)=n(NaOH)/V=0.05mol/0.8mol/L=0.0625L=62.5mL