# A gas confined to a piston is subjected to a pressure that is THREE TIMES as great as the initial pressure. How does the volume evolve given constant temperature?

Jul 15, 2017

Should not the volume REDUCE to a third of the original volume?

#### Explanation:

Old Boyle's Law holds that $P V = k$ at constant temperature and constant amount of gas......

And thus ${P}_{1} {V}_{1} = {P}_{2} {V}_{2}$..................given that we describe a piston containing the SAME amount of gas.........

And if we solve for ${V}_{2} = \frac{{P}_{1} {V}_{1}}{P} _ 2 = \frac{{P}_{1} {V}_{1}}{3 {P}_{1}} = \frac{1}{3} \cdot {V}_{1}$ (because we specify that ${P}_{2} = 3 \times {P}_{1}$).

Does this make sense intuitively, given that we compress a gas at constant temperature?