Physics 2017 JAMB Past Questions - Question 12: The volume of a fixed mass of gas is 10cm when its pressure is 400cmHg.Determine the volume of the gas when its pressure is 200cmHg.

Correct Answer

D

Explanation

P1V1 = P2V2 400 x 10 = 200 x V2V2 = 400 x 10 =20cm3 200
To determine the volume of the gas when its pressure is 200 cmHg, we can use Boyle's Law, which states that the pressure and volume of a gas are inversely proportional when the temperature and the amount of gas remain constant.

According to Boyle's Law, the product of the initial pressure (P1) and the initial volume (V1) is equal to the product of the final pressure (P2) and the final volume (V2). Mathematically, this can be expressed as:

P1 * V1 = P2 * V2

Given that the initial pressure (P1) is 400 cmHg and the initial volume (V1) is 10 cm, we can substitute these values into the equation:

400 cmHg * 10 cm = 200 cmHg * V2

Simplifying the equation, we have:

4000 cmHg = 200 cmHg * V2

Dividing both sides of the equation by 200 cmHg, we get:

V2 = 4000 cmHg / 200 cmHg

V2 = 20 cm

Therefore, the volume of the gas when its pressure is 200 cmHg is 20 cm.