Răspuns:
Explicație:
A.
48 g O
xg Al2 (SO4)3
M Al2 (SO4)3= 2.27 + 3.32 + 12 . 16= 342 ------> 342 g/moli
342g Al2 (SO4)3 ---------192g O
xg----------------------------------48g O
x=- 342 . 48 : 192= 85,5 g Al2 (SO4)3
n= 85,5g : 342g/moli=0,25 moli
B.
2Al(OH)3 +3H2SO4=Al2(SO4)3 +6 H2O
Al2O3 + 3H2SO4= Al2(SO4)3 +3 H2O