Question

When volume of system is increased two times and temperature is decreased half of its initial temperature, then pressure becomes

• A. 2 times
• B. 4 times
• C. 1 / 4 times
• D. 1 / 2 times

Answer 1

Answer: (C)

1 / 4 times

Answer 2

From $PV = \mu RT$ we get $\frac{P_{2}}{P_{1}} = \left( \frac{T_{2}}{T_{1}} \right)\left( \frac{V_{1}}{V_{2}} \right) = \left( \frac{T_{1}/2}{T_{1}} \right)\left( \frac{V_{1}}{2V_{1}} \right) = \frac{1}{4}$ ⇒ $P_{2} = \frac{P_{1}}{4}$