Question

The pressure of gas in 550.0 mL cylinder is 64.2 mm Hg. To what volume must it be compressed to increase the pressure to 390. mm Hg?

Answer 1

We know that PV = nRT

Where

T = Temperature ;P = pressure ; n = No . of moles ;R = gas constant ; V= Volume of the gas

As the gas remains the same , n will constant also temperature be same.

So PV = constant

Thereby PV = P'V'

Where

P = initial pressure = 4.2 mm Hg

V = initial volume = 550.0 mL

P' = final pressure = 390.0 mm Hg

V' = final volume =?

Plug the values we get

V' = (PV) / P'

    = ( 64.2 x 550.0) /390.0

    = 90.5 mL

Therefore the required volume is 90.5 mL