For the reaction,$2Cl_{(g)} \to Cl_{2(g)}$,the signs of $\Delta H$ and $\Delta S$ respectively,are:

Which of the following relations is correct?

Consider the following statements:
Statement-$I$: During isothermal expansion of an ideal gas,its enthalpy decreases.
Statement-$II$: When $2.0 \ L$ of an ideal gas expands isothermally into vacuum,$\Delta U = 0$.

The enthalpy of neutralisation of $KOH$ by a weak acid $(HA)$ is $-12.2 \ kcal \ mol^{-1}$. If the weak acid is $10 \%$ ionised,then the enthalpy of dissociation of $1 \ mole$ of $HA$ is. Given that the enthalpy of neutralisation of $KOH$ by $HCl$ is $-13.7 \ kcal \ mol^{-1}$.

Identify the incorrect statements among the following:
$(a)$ All enthalpies of fusion are positive.
$(b)$ The magnitude of enthalpy change does not depend on the strength of the intermolecular interactions in the substance undergoing phase transformations.
$(c)$ When a chemical reaction is reversed,the value of $\Delta_r H^{\circ}$ is reversed in sign.
$(d)$ The change in enthalpy is dependent on the path between the initial state (reactants) and final state (products).
$(e)$ For most of the ionic compounds,$\Delta_{\text{sol}} H^{\circ}$ is negative.

An ideal gas is allowed to expand both reversibly and irreversibly in an isolated system. If $T_i$ is the initial temperature and $T_f$ is the final temperature,which of the following statements is correct?