Which thermodynamic process is quasi-static and does not dissipate energy?

Which of the following is an irreversible process?

Consider the given diagram. An ideal gas is contained in a chamber (left) of volume $V$ and is at an absolute temperature $T$. It is allowed to rush freely into the right chamber of volume $V$ which is initially vacuum. The whole system is thermally isolated. What will be the final temperature once the equilibrium has been attained?

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

If a Van der Waals gas expands freely,then the final temperature is:

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