At $27\,^{\circ}C$,$1\, mole$ of an ideal gas expands reversibly and isothermally from $2\, atm$ to $1\, atm$. Then $\Delta H$ will be......$kJ$.

Calculate $q$ when $0.75 \ mol$ of an ideal gas expands isothermally and reversibly at $27 \ ^oC$ from a volume of $15 \ L$ to $25 \ L$.
(Given $\log 5 = 0.70, \log 3 = 0.48$)
...... $Joule$

$1 \ mol$ of an ideal gas is allowed to expand isothermally and reversibly from $1 \ L$ to $5 \ L$ at $300 \ K$. The change in enthalpy (in $kJ$) is $(R = 8.3 \ J \ K^{-1} \ mol^{-1})$.

When a solvent is added to a solution,the heat of the solution $...$.

What are extensive properties?

$A$ system is changed from state $A$ to state $B$ by one path and from $B$ to $A$ by another path. If $E_1$ and $E_2$ are the corresponding changes in internal energy,then: