In an isochoric process,the increase in internal energy is

Express the change in internal energy of a system when
$(i)$ No heat is absorbed by the system from the surroundings,but work $(w)$ is done on the system. What type of wall does the system have?
$(ii)$ No work is done on the system,but $q$ amount of heat is taken out from the system and given to the surroundings. What type of wall does the system have?
$(iii)$ $w$ amount of work is done by the system and $q$ amount of heat is supplied to the system. What type of system would it be?

An ideal gas,$\overline{C}_{V} = \frac{5}{2} R$,is expanded adiabatically against a constant pressure of $1 \ atm$ until it doubles in volume. If the initial temperature and pressure are $298 \ K$ and $5 \ atm$,respectively,then the final temperature is . . . . . . $K$ (nearest integer). [$\overline{C}_{V}$ is the molar heat capacity at constant volume]

The heat change for the following reaction at $298 \ K$ and at constant pressure is $+7.3 \ kcal$: $A_2B_{(s)} \to 2A_{(s)} + 1/2B_{2(g)}$,$\Delta H = +7.3 \ kcal$. The heat change at constant volume would be:

For the reaction $C_2H_5OH_{(l)} + 3O_{2(g)} \rightarrow 2CO_{2(g)} + 3H_2O_{(l)}$,the enthalpy change $(\Delta H)$ at $27\,^oC$ is $-1366.5 \,kJ\,mol^{-1}$. What will be the value of the internal energy change $(\Delta U)$ in $kJ\,mol^{-1}$ at the same temperature?

$A$ gas expands against a variable pressure given by $P = \frac{20}{V}$ ($P$ in $atm$ and $V$ in $L$). During expansion from volume of $1 \ L$ to $10 \ L$,the gas undergoes an increase in internal energy of $400 \ J$. How much heat is absorbed by gas during expansion (in $J$)? (Given: $1 \ L \cdot atm = 101.3 \ J$)