In an endothermic reaction,the value of $\Delta H$ is

Fill in the blanks:
$(i)$ $A$ system that allows the exchange of energy but not matter with the surroundings is called a ........ .
$(ii)$ The total amount of energy consisting of the internal energy of a substance plus the product of its pressure and volume is called ........ .
$(iii)$ The change in energy that occurs when a chemical reaction is carried out at constant pressure is called ........ .

On what factors does the enthalpy of dilution of a solution depend?

The heat of combustion of benzene determined in a bomb calorimeter is $-870 \ kcal \ mol^{-1}$ at $25 \ ^oC$. The value of $\Delta E$ for the reaction is......$kcal$.

Under isothermal condition,a gas at $300 \; K$ expands from $0.1 \; L$ to $0.25 \; L$ against a constant external pressure of $2 \; bar$. The work done by the gas is .... [Given that $1 \; L \; bar = 100 \; J$]

The work done when $2 \ mol$ of an ideal gas expands reversibly and isothermally from a volume of $1 \ L$ to $10 \ L$ at $300 \ K$ is $(R = 0.0083 \ kJ \ K^{-1} \ mol^{-1})$ (in $kJ$)