Question

With the temperature held constant, the piston of a cylinder containing a gas is pulled out so that the volume increases from 0.3 m3 to 0.9 m3. If the final pressure of the gas is 80 kPa, what was the initial pressure

Answer 1

Answer:

P1 = 240 kPa.

Explanation:

Given the following data;

Initial volume = 0.3 m³

Final volume, V2 = 0.9 m³

Final pressure, P2 = 80 kPa

To find the initial pressure, we would use Boyle's law;

Boyles states that when the temperature of an ideal gas is kept constant, the pressure of the gas is inversely proportional to the volume occupied by the gas.

Mathematically, Boyles law is given by the formula;

$PV = K$

$P_{1}V_{1} = P_{2}V_{2}$

Substituting into the formula, we have;

$P_{1} * 0.3 = 80 * 0.9$

$0.3P_{1} = 72$

$P_{1} = \frac {72}{0.3}$

$P_{1} = 240$

Therefore, the initial pressure of the gas is 240 kPa