If the enthalpy of $B$ is greater than that of $A$,the reaction $A \to B$ is

Which of the following processes involves zero work done?

$1 \text{ mole}$ of an ideal gas is compressed isothermally and reversibly from an initial pressure $x \text{ kPa}$ to a final pressure $2x \text{ kPa}$ at $300 \text{ K}$. Find the work done $(R = 8.314 \text{ J K}^{-1} \text{mol}^{-1})$. (in $\text{ J}$)

Fill in the blanks:
$(i)$ $1 \ \text{calorie} = \ldots \ldots \ \text{joules}$
$(ii)$ The work done by the system can be calculated by the equation .......

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 $\log 5 = 0.70, \log 3 = 0.48$)
...... $Joule$

In an endothermic reaction,the value of the change in enthalpy $(\Delta H)$ is