$A$ balloon filled with helium ($32^{\circ} C$ and $1.7 \; atm$) bursts. Immediately afterwards,the expansion of helium can be considered as:

$A$ container with insulating walls is divided into two equal parts by a partition fitted with a valve. One part is filled with an ideal gas at a pressure $P$ and temperature $T$,whereas the other part is completely evacuated. If the valve is suddenly opened,the pressure and temperature of the gas will be

$Assertion :$ Thermodynamic processes in nature are irreversible.
$Reason :$ Dissipative effects cannot be eliminated.

$A$ container with rigid walls is covered with perfectly insulating material. The container is divided into two parts by a partition. One part contains a gas while the other is fully evacuated (vacuum). The partition is suddenly removed. The gas rushes to fill the entire volume and comes to equilibrium after a little time. If the gas is not ideal,then

Which of the following processes is reversible?

For a reversible process,the necessary condition is: