QUESTION TWO

A$.$ Define a reversible process.

$[3$ Marks$]$

B$.$ A quantity of a gas occupies a volume of $0\mathrm{.}4m^3$ at a pressure of $100K\frac{N}{m^3}$ and temperature of $20C.$ The gas is compressed isothermally to a pressure of $450K\frac{N}{m^2},$ and then expanded adiabatically to its initial volume. Determine for this quantity of gas;

$($i$)$ The heat received or rejected $($state which$)$ during the compression.

$($ii$)$ The change in internal energy during the expansion.

$[6$ Marks$]$

$($iii$)$ The mass of the gas.

$[6$ Marks$]$

Assume that $=1\mathrm{.}4$ and $C_P=1\mathrm{.}0K\frac{J}{K}gK,$ and that the gas is perfect.

$[5$ Marks$]$

$($TOTAL $20$ Marks$)$