We have 35 g of ice at a temperature of -15 how much heat is needed for this substance to completely melt

Initial data: m (ice mass) = 35 g = 0.035 kg; t0 (initial ice temperature) = -15 ºС.

Reference data: C (specific heat capacity of ice) = 2100 J / (kg * K); λ (specific heat of melting of ice) = 340 * 10 ^ 3 J / kg; tmelt (ice melting temperature) = 0 ºС.

Required amount of heat:

Q = Q1 (ice heating) + Q2 (ice melting) = C * m * (tmelt – t0) + λ * m = m * (C * (tm – t0) + λ).

Let’s perform the calculation:

Q = 0.035 * (2100 * (0 – (-15)) + 340 * 10 ^ 3) = 13002.5 J ≈ 13 kJ.

Answer: You need 13 kJ of heat.