What amount of heat will be released during the crystallization of 200 g of water at a temperature of 0 ° C?

The desired heat released during the crystallization of a given mass of water can be calculated using the following formula (there is no temperature change, the water transitions from one state to another):

Q = λ * m, where according to the condition of the problem λ (specific heat of crystallization (melting)) = 3.4 * 10 ^ 5 J / kg, m (mass) = 200 g or 0.2 kg.

Let’s perform the calculation:
Q = λ * m = 3.4 * 10 ^ 5 * 0.2 = 0.68 * 10 ^ 5 J = 68 * 10 ^ 3 J = 68 kJ.

Answer: When water crystallizes, 68 kJ of heat is released.