$A$ certain mass of a gas was brought from state $A$ to $B$ by following three different paths,namely $1$,$2$ and $3$,respectively. Which of the following relations is correct for the work done?

In an exothermic reaction,the reactants:

Which of the following is an isolated system?

For a change in state of $1 \, \text{mole}$ of a non-ideal gas,the change in internal energy is $\Delta U = 30.0 \, \text{L} \cdot \text{atm}$. The state changes from $(2.0 \, \text{atm}, 3.0 \, \text{L}, 95 \, \text{K})$ to $(4.0 \, \text{atm}, 5.0 \, \text{L}, 245 \, \text{K})$. What is the change in enthalpy $(\Delta H)$ in $\text{L} \cdot \text{atm}$?

Define open,closed,and isolated systems with examples.

What is molar enthalpy of vaporization?