Дано:
Na2O
Al2O3
P2O3
W(O)-?
M(Na2O)=23*2+16=62 W(O)=23*2/62=0,74(74%)
М(Al2O3)=27*2+16*3=102 W(O)=27*2/102=0,53(53%)
М(P2O3)=31*2+16*3=110 W(O)=31*2/110=0,56(56%)
2CH3-COONa+NaHCO3-->CH4+2Na2CO3
Ba(OH)2 + K2CO3 = BaCO3↓ + 2KOH
Fe + CuSO4 = FeSO4 + Cu<span>↓
Ответ: </span>a и d
Mg(OH)2 + 2HCl — MgCl2 + 2H2O
Mg(OH)2 + 2H (+) + 2Cl (-) — Mg (2+) + 2Cl (-) + 2H2O
Mg(OH)2 + 2H (+) — Mg (2+) + 2H2O