What will be the $\Delta U$ value, when one mole of oxygen $(O_2)$ is heated from $-20^{\circ} C$ to $40^{\circ} C$ at constant volume (in $J$)? (Molar heat capacity for oxygen $\simeq 20.8 \ J \ mol^{-1} \ K^{-1}$)

Define specific heat capacity and provide examples of intensive properties.

The molar heat capacity of water at constant pressure is $75 \ J \ K^{-1} \ mol^{-1}$. When $1.0 \ kJ$ of heat is supplied to $100 \ g$ of water which is free to expand,the increase in temperature of water is $...... \ K$.

The molar heat capacity of water in equilibrium with ice at constant pressure is.....

For the reaction ${H_2}_{(g)} + \frac{1}{2}{O_2}_{(g)} \to {H_2}O(\ell)$,given $\Delta C_P = 7.63 \, cal/deg$ and $\Delta H_{25\,^{\circ}C} = 68.3 \, Kcal$,find the value of $\Delta H$ at $100\,^{\circ}C$ (in $Kcal$).

$A$ piece of metal weighing $100 \, g$ is heated to $80^{\circ} C$ and dropped into $1 \, kg$ of cold water in an insulated container at $15^{\circ} C$. If the final temperature of the water in the container is $15.69^{\circ} C$,the specific heat of the metal in $J / g \cdot ^{\circ} C$ is