N = w/ Ar
N (Al) = 53 / 27 = 2
N ( O) = 47/16 = 3
Al2O3
:)
Сольваты...........................
Na₂O+2HCI=2NaCI+H₂O
3KOH+Fe(OH)₃=K₃[Fe(OH)₆]
2LiOH+H₂SO₄=Li₂SO₄+2H₂O
K₂O+H₂O=2KOH