In a glass beaker weighing 120 g, having a temperature of 15, poured 200 g of water at a temperature of 100.

In a glass beaker weighing 120 g, having a temperature of 15, poured 200 g of water at a temperature of 100. At what temperature the thermal equilibrium will be established.

Given:

m1 = 120 grams = 0.12 kilograms – the mass of cold water;

T1 = 15 ° Celsius – cold water temperature;

m2 = 200 grams = 0.2 kilograms – the mass of hot water;

T2 = 100 ° Celsius – hot water temperature.

It is required to determine T (degree Celsius) – the temperature of the mixture.

To determine the temperature of the mixture, you must use the following formula:

Q1 = Q2;

c * m1 * (T – T1) = c * m2 * (T2 – T), where c is the specific heat capacity of water;

m1 * T – m1 * T1 = m2 * T2 – m2 * T;

m1 * T + m2 * T = m2 * T2 + m1 * T1;

T * (m1 + m2) = m2 * T2 + m1 * T1;

T = (m2 * T2 + m1 * T1) / (m1 + m2) = (0.2 * 100 + 15 * 0.12) / (0.2 + 0.12 = (20 + 1.8) / 0 .32 = 21.8 / 0.32 = 68.1 ° Celsius.

Answer: The temperature of the mixture will be 68.1 ° Celsius.