$A$ container of volume $1 \ m^3$ is divided into two equal compartments by a partition. One of these compartments contains an ideal gas at $300 \ K$. The other compartment is vacuum. The whole system is thermally isolated from its surroundings. The partition is removed and the gas expands to occupy the whole volume of the container. Its temperature now would be ..... $K$.

Given below are two statements. One is labelled as Assertion $(A)$ and the other is labelled as Reason $(R)$.
Assertion $(A) :$ In an insulated container,a gas is adiabatically shrunk to half of its initial volume. The temperature of the gas decreases.
Reason $(R) :$ Free expansion of an ideal gas is an irreversible and an adiabatic process.
In the light of the above statement,choose the correct answer from the options given below :

$A$ closed container is fully insulated from the outside. One half of it is filled with an ideal gas $X$ separated by a plate $P$ from the other half $Y$,which contains a vacuum as shown in the figure. When $P$ is removed,$X$ expands into $Y$. Which of the following statements is correct?

What is a quasi-static process?

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

$Assertion :$ Reversible systems are difficult to find in the real world.
$Reason :$ Most processes are dissipative in nature.