What type of changes occur in an object by heating it?

$A$ thermocouple produces $40 \, \mu V/K$. The temperatures of the cold and hot junctions are $40 \, ^\circ C$ and $20 \, ^\circ C$ respectively. If $150$ such thermocouples are connected in series,what is the total thermo-emf produced in $mV$?

The temperature at which the vapour pressure of a liquid becomes equal to the external (atmospheric) pressure is its

$5 \text{ g}$ of steam at $100^{\circ} \text{C}$ is mixed with $5 \text{ g}$ of ice at $0^{\circ} \text{C}$. What is the final temperature of the mixture (in $^{\circ} \text{C}$)?

Dry ice is

The height of a waterfall is $84 \, m$. Assuming that the entire kinetic energy of falling water is converted into heat, the rise in temperature of the water will be $(g = 9.8 \, m/s^2, J = 4.2 \, J/cal, c = 1 \, cal/g^\circ C = 4200 \, J/kg^\circ C)$. (in $^\circ C$)