Question

A container with 3 kg of pure water at a temperature of 12 degrees Celsius is placed in a refrigerator where the air temperature is kept at 4 degrees Celsius. how much heat (in joules) is gained by the air when the water cools to 4 degrees Celsius?

Answer 1

The air gains 100.224 J of heat when the water cools to 4 degrees Celsius.

Step-by-step explanation:

To calculate the heat gained by the air, we can use the equation q = mcΔT, where q is the heat gained, m is the mass, c is the specific heat capacity, and ΔT is the temperature change.

First, we need to calculate the heat gained by the water as it cools from 12 degrees Celsius to 4 degrees Celsius. We know that the specific heat capacity of water is 4.184 J/g °C.

1. Calculate the mass of the water: mass = 3 kg.
2. Calculate the temperature change: ΔT = 12 - 4 = 8 degrees Celsius.
3. Calculate the heat gained by the water: q = 3 kg × 8 °C × 4.184 J/g °C = 100.224 J.

Therefore, the air gains 100.224 J of heat when the water cools to 4 degrees Celsius.

Answer 2

100 368 J

Step-by-step explanation:

Heat lost by the water = heat gained by the air ( which the 'frige works to expel and keep at 4 degrees)

specific heat for water ( in joules) : 4182 J / kg-C

3 kg * 4182 J / kg-C * (12-4 C) = 100 368 J