How much heat must be imparted to a piece of ice with a mass of 2.5 kg

How much heat must be imparted to a piece of ice with a mass of 2.5 kg in order to completely melt it, and heat the resulting water to 85 degrees?

Given:

m = 2.5 kilograms is the mass of ice;

q = 3.4 * 10 ^ 5 J / kg – specific heat of ice melting;

c = 4220 J / (kg * deg) – specific heat capacity of water;

T = 85 degrees Celsius.

It is required to find the amount of energy Q (Joule), which is required to melt the ice and heat it to the temperature T.

It takes energy to melt ice:

Q1 = q * m = 3.4 * 10 ^ 5 * 2.5 = 8.5 * 10 ^ 5 Joules.

To heat the resulting water, you will need to expend energy:

Q2 = c * m * T = 4220 * 2.5 * 85 = 9 * 10 ^ 5 Joules.

In total, you need to spend energy:

Q = Q1 + Q2 = 8.5 * 10 ^ 5 + 9 * 10 ^ 5 = 17.5 * 10 ^ 5 Joules = 1.8 MJ.

Answer: you need to spend 1.8 MJ of energy.