The temperature of an object is a measure of its hotness or coldness - Leaving Cert Physics - Question 9 - 2012

The relationship between Celsius and Kelvin is given by the formula:
$heta(°C) = T(K) - 273.15$
Thus, to convert from Celsius to Kelvin, add 273.15.

Heat is a form of energy that is transferred between substances or systems due to a temperature difference.

The three methods of heat transfer are conduction, convection, and radiation.

The change in the state of a substance refers to any change between solid, liquid, or gas states.

Specific latent heat is the amount of energy required to change 1 kg of a substance from one state to another without a change in temperature.

To calculate the energy required to melt the ice, use the formula:
$E = mL$
where:
m = mass of the ice = 20 g = 0.020 kg
L = specific latent heat of fusion = 3.34 x 10^5 J/kg
Thus,
$E = 0.020 imes 3.34 imes 10^5 = 6680 ext{ J}$.

To find the energy required to raise the temperature of the melted ice to 5 °C, use:
$E = mc heta$
where:
m = 0.020 kg,
c = specific heat capacity of water = 4180 J/(kg·K),
$heta = 5 °C - 0 °C = 5 K$.
So,
$E = 0.020 imes 4180 imes 5 = 418 ext{ J}$.

Stirring the mixture ensures uniform temperature distribution throughout the water, preventing any localized areas from freezing or remaining warmer than others.