ajutatima varog stabileste valenta elementului in baza formulei chimice.(cunoscind valenta altui element sau grupe de elemente) a) N₂O Cu(OH)₂ Al₂(SO₄)₃ B) SO₂ Al₂ O₃ Ca(OH)₂ C) SO₃ CaCl₂ Fe Cl₃
a)O are -2 iar N are 1 (OH) are -1 Cu are 2 SO4 are -2 Al are 3 B)O are -2 S are 4 O are -2 Al are 3 OH are -1 Ca are 2 C) O are -2 S are 6 Cl are -1 Ca are 2 Cl are -1 Fe are 3
