Question

At a constant temperature , a gas is at a pressure of 1080 mm of Hg . If the volume is decreased by 40% , find the new pressure of the gas .

Answer 1

Step 1:

Given that:

Initial pressure of gas $P_1$ = 1080 mm of Hg

Let the initial volume ($V_1$) be V.

Volume decreased to 40%

Then final volume ($V_2$) will be 40% of V = 0.4 V

Step 2:

The temperature is constant here. Boyle's law is used which state about the relationship between the pressure and volume of a gas.

According to Boyle's law:

$P_1{V}_1=P_2{V}_2$

Step 3:

By putting the values in the formula.

$1080\times V=P_2\times 0.4V$

$\frac{1080}{P_2}=\frac{0.4V}{V}$

$\frac{1080}{P_2}=0.4$

$P_2=2700mmofHg$

Hence, the new pressure of the gas will be 2700 mm of Hg.