The energy diagram for a reaction $R \to P$ is shown below. The $\Delta H^o$ for the reaction will be:

Fill in the blanks:
$(i)$ The conversion of graphite into diamond is a ........ process.
$(ii)$ $1 \text{ calorie} = ........ \text{ Joules}$.
$(iii)$ Work done by the system can be calculated by the equation ........ .
$(iv)$ The change in heat energy during a chemical reaction at constant volume is called ........ .

Define open,closed,and isolated systems with examples.

Calculate work done if $1 \ mole$ of an ideal gas expands isothermally from $2 \ dm^3$ to $2.8 \ dm^3$ against constant external pressure $1 \ atm$. (in $J$)

Fill in the blanks:
$(i)$ During the ........... process,there is no absorption or evolution of heat.
$(ii)$ The equation $\Delta G = \Delta H - T\Delta S$ was proposed by ........... .

Enthalpy change for freezing of $1 \ g$ of water at $1 \ bar$ and $0^{\circ} C$ is $334 \ J$. Calculate the internal energy change in $J$ when $1 \ g$ of water is converted into ice?