How much firewood do you need to burn in order to completely turn a 200g piece of ice into water vapor?

How much firewood do you need to burn in order to completely turn a 200g piece of ice into water vapor? Consider that 10% of the heat released during combustion is used for heating.

Data: m1 (mass of a piece of ice, water) = 200 g = 0.2 kg; t0 (initial ice temperature) = 0 ºС; η = 10% = 0.1.

Reference values: q (specific heat of combustion of wood) = 10 * 10 ^ 6 J / kg; λ (specific heat of fusion) = 3.4 * 10 ^ 5 J / kg; C (specific heat) = 4200 J / (kg * K); L (specific heat of vaporization) = 2.3 * 10 ^ 6 J / kg.

Efficiency: η = m * (λ + C * 100 + L) / (q * m1).

m1 = m * (λ + C * 100 + L) / (η * q) = 0.2 * (3.4 * 10 ^ 5 + 4200 * 100 + 2.3 * 10 ^ 6) / (0.1 * 10 * 10 ^ 6) = 0.612 kg = 612 g.