What is constant in an adiabatic process?

When $2 \text{ moles}$ of a monatomic gas expands adiabatically from a temperature of $80^{\circ} C$ to $50^{\circ} C$,the work done is $W$. The work done when $3 \text{ moles}$ of a diatomic gas expands adiabatically from $50^{\circ} C$ to $20^{\circ} C$ is: (in $W$)

$A$ monoatomic ideal gas undergoes an adiabatic process at room temperature. The relation between temperature and volume is $TV^{x} = \text{constant}$, then $x$ is

$A$ gas for which $\gamma = 1.5$ is suddenly compressed to $\frac{1}{4}$ of its initial volume. What is the ratio of the final pressure to the initial pressure?

$A$ graph of pressure versus volume for an ideal gas for different processes is as shown. In the graph,curve $OC$ represents:

$Assertion:$ When a bottle of cold carbonated drink is opened,a slight fog forms around the opening.
$Reason:$ Adiabatic expansion of the gas causes lowering of temperature and condensation of water vapours.