Question

Calculate the mass of ice needed to cool 150 g of water contained in a calorimeter of mass 50 g at 32 °C such that the final temperature is 5 °C .

Specific heat capacity of calorimeter = 0.4 J/g°C

Specific heat capacity of water = 4.2 J/g°C

Latent heat capacity of ice = 330 J/g

Answer 1

Heat energy imparted by calorimeter and water contained in it in cooling from 32°C to 5°C is used in melting ice and then raising the temperature of melted ice from 0°C to 5°C.

From the principle of calorimetiy, if the system is fully insulated then, Heat gained by cold body = Heat lost by hot body.

∴ The mass of ice needed =50 g.