Question

At constant temperature for fixed amount of gas, what happens to the pressure when the volume is doubled?

• A. It is halved
• B. It is quadrupled
• C. It is doubled
• D. It cannot be predicted
• E. It remains unchanged

Answer 1

The correct option is A It is halved

The ideal gas equation is $PV=nRT$.
At constant temperature, for a fixed amount of a gas, $P\propto \frac{1}{V}$
Thus, pressure is inversely proportional to volume.
When volume is doubled, pressure is reduced to one half.
Hence, the option (A) is the correct answer.