Entropy — Prelims Questions

One mole of an ideal gas expands isothermally and reversibly from an initial volume $V$ to a final volume $2V$ at a constant temperature of $300\,\text{K}$. What is the change in entropy of the gas? (Given: Universal gas constant $R = 8.314\,\text{J/mol K}$)

A $100\,\text{g}$ block of ice at $0^\circ C$ melts completely to water at $0^\circ C$. If the latent heat of fusion of ice is $334\,\text{J/g}$, what is the change in entropy of the ice during this process?

Which of the following statements about entropy is INCORRECT?

An isolated system undergoes a change. Which of the following is true regarding its entropy?

Which of the following processes results in a decrease in the entropy of the system?

Calculate the change in entropy when $2\,\text{moles}$ of an ideal monatomic gas are heated from $300\,\text{K}$ to $400\,\text{K}$ at constant volume. (Given: $R = 8.314\,\text{J/mol K}$, $C_v = \frac{3}{2}R$ for a monatomic gas)