JAMB Chemistry 2023 Paper

Concept:Boyle’s law states that at constant temperature, the pressure and volume of a fixed mass of gas are inversely proportional. Therefore, $P_1V_1 = P_2V_2$.Explanation:Initial pressure, $P_1 = 2 \, \text{atm}$.Initial volume, $V_1 = 1.5 \, \text{L}$.Final pressure, $P_2 = 4 \, \text{atm}$.Final volume, $V_2$ is unknown.Using Boyle’s law:$$P_1 V_1 = P_2 V_2$$$$2 \, \text{atm} \times 1.5 \, \text{L} = 4 \, \text{atm} \times V_2$$$$3 \, \text{atm} \cdot \text{L} = 4 \, \text{atm} \times V_2$$$$V_2 = \frac{3 \, \text{atm} \cdot \text{L}}{4 \, \text{atm}} = 0.75 \, \text{L}$$When the pressure doubles from $2 \, \text{atm}$ to $4 \, \text{atm}$, the volume is halved.Answer:The new volume of the gas is $0.75 \, \text{L}$.Correct option: C. $0.75$ liters.