(i) From HgO

Balanced equation: 2HgO → 2Hg + O₂

Molar mass of HgO = 200 + 16 = 216 g/mol

From the equation,

2 × 216 g HgO produces 32 g O₂

Therefore, 216 g HgO produces = \frac{32\times216}{2\times216} = 16 g O₂

Now,

Balanced equation for KClO₃:

2KClO₃ → 2KCl + 3O₂

Molar mass of KClO₃ = 39 + 35.5 + (16 × 3)

= 122.5 g/mol

From the equation,

2 × 122.5 g KClO₃ produces 3 × 32 g O₂

Therefore, mass of KClO₃ required to produce 16 g O₂

= \frac{2\times122.5\times16}{3\times32}

= 40.83 g

Hence, 40.83 g of KClO₃ must be heated.