If $5 \ kJ$ of work is done on the system and $1 \ kJ$ of heat is released by the system,find the change in internal energy in $kJ$.

The volume of an ideal gas contracts from $10.0 \ L$ to $2.0 \ L$ under an applied pressure of $2.0 \ atm$. During contraction,the system also evolved $900 \ J$ of heat. The change in internal energy (in $J$) involved in the system is $(1 \ L \ atm = 101.3 \ J)$:

$A$ gaseous sample expands from $200 \, cm^3$ to $500 \, cm^3$ against a constant external pressure of $750 \, torr$ while absorbing $1.5 \, J$ of heat. What is the change in internal energy of the system in $J$? $(1 \, atm \cdot L = 101.3 \, J)$

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?

An ideal gas absorbs $210 \ J$ of heat and undergoes expansion from $3 \ L$ to $6 \ L$ against a constant external pressure of $10^5 \ Pa$. What is the value of $\Delta U$ (in $J$)?

Which of the following statements is true regarding the universe according to the laws of thermodynamics?