What is the value of the specific heat of a solid by using the law of equipartition of energy?

Why is water used as a coolant?

$100 \ g$ of water is heated from $30^\circ C$ to $50^\circ C$. Ignoring the slight expansion of the water,the change in its internal energy is .......$kJ$ (specific heat of water is $4184 \ J/kg/K$):

How much heat energy is gained when $5\, kg$ of water at $20^{\circ}C$ is brought to its boiling point? (Specific heat of water $= 4.2\, kJ\, kg^{-1} {^{\circ}C}^{-1}$)

The temperature of $5$ moles of a gas which was held at constant volume was changed from $100^{\circ}C$ to $120^{\circ}C$. The change in internal energy was found to be $80$ Joules. The total heat capacity of the gas at constant volume will be equal to ...... $J/K$.

$50 \text{ g}$ of copper is heated to increase its temperature by $10^{\circ} \text{C}$. If the same quantity of heat is given to $10 \text{ g}$ of water,the rise in temperature is (specific heat of $\text{Cu} = 420 \text{ J kg}^{-1} {}^{\circ} \text{C}^{-1}$ and specific heat of water is $4200 \text{ J kg}^{-1} {}^{\circ} \text{C}^{-1}$) (in $^{\circ} \text{C}$)