5. Mr ((NH4)2CO3) =

Mr ((NH4)2CO3) = 2 × (Ar(N) + 4 × Ar(H)) + Ar(C) + 3 × Ar(O) = 2 × (14 + 4 × 1) + 12 + 3 × 16 = 2 × 18 + 12 + 48 = 36 + 12 + 48 = 96

Ответ: 96