How much heat must be imparted to water weighing 1 kg in order to heat it from 10 degrees to 20C?

Given: m (mass of water to be heated) = 1 kg; t1 (temperature before heating) = 10 ºС; t2 (final heating temperature) = 20 ºС.

Constant values: according to the condition, we take C (specific heat capacity of water) = 4200 J / (kg * ºС).

The amount of heat that is needed for heating is calculated by the formula: Q = C * m * Δt = C * m * (t2 – t1).

Let’s make the calculation: Q = 4200 * 1 * (20 – 10) = 42,000 J (42 kJ).

Answer: c) you need 42,000 J (42 kJ) heat.