Question

Помогите с первым заданием.

Answer 1

Na2S + CuSO4 -> CuS↓ + Na2SO4
2Na(+) + S(-2) + Cu(+2) + SO4(-2) -> CuS↓ + 2Na(+) + SO4(-2)
Cu(+2) + S(-2) -> CuS↓

Answer 2

Na₂S + CuSO₄ = Na₂SO4 + CuS↓
2Na⁺+S²⁻+Cu²⁺+SO₄²⁻ = 2Na⁺+SO₄²⁻ + CuS↓
Cu²⁺+S²⁻ = CuS↓