Which of the following is an extensive property?

Assertion : During an adiabatic process,heat energy is not exchanged between the system and its surroundings.
Reason : The temperature of a gas increases when it undergoes an adiabatic expansion.

The enthalpies of all elements in their standard states are:

Which of the following sets represents the normal physical states of the elements concerned at $25\,^{\circ}C$ and $1 \ bar$ pressure,for which $\Delta H^{\circ}_{f} = 0$?

$6$ moles of an ideal gas expand isothermally and reversibly from a volume of $1$ litre to a volume of $10$ litres at $27\,^oC$. What is the maximum work done (in $, kJ$)?

If a gas expands at constant temperature and pressure,then its: