In a metal vessel there was 400 g of water at a temperature of 15 C. Another 220 g of water was poured

In a metal vessel there was 400 g of water at a temperature of 15 C. Another 220 g of water was poured into it at a temperature of 69 C. The temperature of the mixture became equal to 33 C. How much heat was used to heat the vessel?

The amount of heat that went to heat the vessel:

Q = Q1 – Q2, where Q1 is the heat given off by hot water, Q2 is the heat given off by cold water.

Q1 = C * m1 * (tн1 – tк1), where C is the specific heat capacity of water (C = 4200 J / (K * kg)), m1 is the mass of water (m1 = 220 g = 0.22 kg), tн1 = 69 ºС, tк1 = 33 ºС.

Q2 = C * m2 * (tк2 – tн2), where m2 is the mass of water (m1 = 400 g = 0.4 kg), tк2 = 33 ºС, tн2 = 15 ºС.

Q = Q1 – Q2 = 4200 * 0.22 * (69 – 33) – 4200 * 0.4 * (33 – 15) = 33264 – 30240 = 3024 J.