How much energy is required to raise the temperature of 3kg of iron from 20 degrees Celsius to 25 degrees Celsius

6750 J

Explanation:

The specific heat capacity of iron is 450 J/kg/K

Quantity of heat = mcθ; where m is the mass and c is the specific heat capacity and θ is the temperature change.

Therefore;

m = 3 kg, c = 450 J/kg/K and θ = 5°C

Quantity of heat = 3 * 450 * 5

= 6150 Joules