What mass of gunpowder must be taken so that after its combustion there is enough

What mass of gunpowder must be taken so that after its combustion there is enough heat to turn 1 kg of ice with a temperature of -20 degrees into steam?

Given: m2 (ice mass) = 1 kg; t0 (initial ice temperature) = -20 ºС.

Constants: q (heat of combustion of gunpowder) = 0.38 * 10 ^ 7 J / kg; Сl (heat capacity of ice) = 2100 J / (kg * K); λ (heat of melting of ice) = 3.4 * 10 ^ 5 J / kg; Cw (heat capacity of water) = 4200 J / (kg * K); L (heat of steam water) = 2.3 * 10 ^ 6 J / kg.

Propellant mass: m1 = (Сl * (0 – t0) + λ + Сv * (100 – 0) + L) * m2 / q = (2100 * (0 – (-20)) + 3.4 * 10 ^ 5 + 4200 * (100 – 0) + 2.3 * 10 ^ 6) * 1 / (0.38 * 10 ^ 7) = 3102000 / (0.38 * 10 ^ 7) = 0.816 kg (816 g).