Question

Balance the equations given below:
1. ZnS + O₂ → ZnO + SO₂
2. K₂Cr₂O₇ + H₂SO₄ + SO₂ → K₂SO₄ + C₂(SO₄)₃ + H₂O
3. Pb(NO₃)₂
——heat–→ PbO + NO₂ + O₂

Answer 1

Balanced equations

Explanation:

1. 2ZnS + 3O₂ → 2ZnO + 2SO₂

2 molecules of ZnS and 3 molecules of O2 gives 2 molecules of ZnO and 2 molecules of SO2.

2. K₂Cr₂O₇ + H₂SO₄ + 3SO₂ → K₂SO₄ + C₂(SO₄)₃ + H₂O

One molecule of K2Cr2O7, one molecule of H2SO4, and 3 molecules of SO2 gives one molecule of K2SO4, one molecule of C2(SO4)3 and a molecule of water

3. 2Pb(NO₃)₂ ——heat–→ 2PbO + 4NO₂ + O₂

Two molecules of Pb(NO3)2 when heated gives 2 molecules of PbO, four molecules of NO2 and a molecule of oxygen