Balance the following equations: (a) Fe + CuSO4 -> .... + .... (b) MnO2 + HCl -> .... + H2O + .... Write the reaction for thermal decomposition of Lead nitrate and names of products formed.

5(ii)(a)

Step 1: Write the unbalanced equation.
$Fe + CuSO_4 \to FeSO_4 + Cu$

Step 2: Check atoms on both sides.
Left: Fe = 1, Cu = 1, S = 1, O = 4
Right: Fe = 1, Cu = 1, S = 1, O = 4

Balanced as is.

Balanced equation:
$Fe + CuSO_4 \to FeSO_4 + Cu$

\mathrm{Fe + CuSO_4 \to FeSO_4 + Cu}

5(ii)(b)

Step 1: Write the unbalanced equation.
$MnO_2 + HCl \to MnCl_2 + H_2O + Cl_2$

Step 2: Balance Mn: coefficient 1 on both (already).
$MnO_2 + HCl \to MnCl_2 + H_2O + Cl_2$

Step 3: Balance O: 2 on left, so 2 H₂O on right.
$MnO_2 + HCl \to MnCl_2 + 2H_2O + Cl_2$

Step 4: Balance H: 4 on right (from 2H₂O), so 4 HCl on left.
$MnO_2 + 4HCl \to MnCl_2 + 2H_2O + Cl_2$

Step 5: Balance Cl: 4 on left, 2 from MnCl₂ + 2 from Cl₂ = 4 on right.

Balanced equation:
$MnO_2 + 4HCl \to MnCl_2 + Cl_2 + 2H_2O$

\mathrm{MnO_2 + 4HCl \to MnCl_2 + Cl_2 + 2H_2O}

6(i)

Step 1: Thermal decomposition of lead nitrate.
Unbalanced: $Pb(NO_3)_2 \to PbO + NO_2 + O_2$

Step 2: Balance Pb: 2 on left, so 2 PbO on right.
$2Pb(NO_3)_2 \to 2PbO + NO_2 + O_2$

Step 3: N: 4 on left, 4 NO₂ on right.
$2Pb(NO_3)_2 \to 2PbO + 4NO_2 + O_2$

Step 4: O: left 12, right 2(1) + 4(2) + 2(1)/2 wait, O₂ is 2O. Right: 2PbO=2O, 4NO₂=8O, O₂=2O total 12O. Balanced.

IUPAC names of products:
lead(II) oxide, nitrogen dioxide, dioxygen

Reaction:
$2Pb(NO_3)_2 ->[heat] 2PbO + 4NO_2 + O_2$

2Pb(NO_3)_2 ->[Δ] 2PbO + 4NO_2 + O_2

6(ii)(a)

Step 1: Identify structure: CH₃-CH₂-CHO (three carbons, aldehyde).

IUPAC name: propanal

propanal