Question

At 25°C, gas in a rigid cylinder with a movable piston has a volume of 145 mL and a pressure of 125 kPa. Then the gas is compressed to a volume of 80. mL. What is the new pressure of the gas if the temperature is held at 25°C?(1) 69 kPa (3) 160 kPa (2) 93 kPa (4) 230 kPa

The first person didn't make sense as P1v1 = P2v2 isnt the same thing as P1V1/V2 that literally doesn't make sense, so could someone help me please!

Answer 1

(4) 230 kPa

Step-by-step explanation:

The temperature is constant, so the only variables are pressure and volume.

We can use Boyle’s Law.

`p_(1)V_(1) = p_(2)V_(2)`

Divide both sides of the equation by
`V_(2)`.

`p_(2) = p_(1) * (V_(1))/( V_(2))`

`p_(1) = \text{145 kPa}; V_(1) = \text{125 cm}^(3)}`

`p_(2) = ?; V_(2) = \text{80. cm}^(3)`

`p_(2) = \text{145 kPa} * \frac{\text{125 cm}^(3)}{\text{80. cm}^(3)} = \textbf{230 kPa}`