$A$ pure substance (solid,liquid,or gas) of constant composition is taken in a closed container. Select the correct plot if pressure is applied at constant temperature in the absence of non-expansion work.

$2 \, mol$ of zinc is dissolved in $HCl$ at $25 \, ^\circ C$. The work done in an open vessel is:

An ideal gas undergoes a reversible isothermal expansion from state $I$ to state $II$ followed by a reversible adiabatic expansion from state $II$ to state $III$. The correct plot$(s)$ representing the changes from state $I$ to state $III$ is(are)
($p$ : pressure,$V$ : volume,$T$ : temperature,$H$ : enthalpy,$S$ : entropy)

Calculate the enthalpy change when $50 \ mL$ of $0.01 \ M$ $Ca(OH)_2$ reacts with $25 \ mL$ of $0.01 \ M$ $HCl$. Given that $\Delta H^o_{\text{neutralisation}}$ of strong acid and strong base is $-57.1 \ kJ \ mol^{-1}$. [Assuming that $Ca(OH)_2$ is a strong base]

The heat of reaction for $C_2H_2 + H_2 \rightarrow C_2H_4$ is given by the following data:
$(i) \Delta H_f^o \text{ of } H_2O_{(\ell)} = -68.3 \ K \ cal \ mol^{-1}$
$(ii) \Delta H_{comb}^o \text{ of } C_2H_2 = -337.2 \ K \ cal \ mol^{-1}$
$(iii) \Delta H_{comb}^o \text{ of } C_2H_4 = -363.7 \ K \ cal \ mol^{-1}$

The enthalpy of combustion of carbon monoxide at $17 ^\circ C$ and constant volume is $-283.3 \ kJ$. Calculate the enthalpy of combustion at constant pressure in $kJ$.