Question

a sample of nitrogen occupies a volume of 200 ml at 60°C and 500 mmHg of pressure. wht will its volume be at STP

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

So PV / T = constant

Thereby PV/T = P'V'/T'

Where

P = initial pressure = 500 mm Hg since 1 atm = 760 torr

                            = 500/760 atm

= 0.658 atm

V = initial volume = 200 mL

T = initial temperature = 60 ^oC = 60+273 = 333 K

P'= final pressure = 1.00 atm

V' = final volume = ?

T' = final temperature = 273 K

Plug the values we get

V' = ( PVT') / ( TP')

= 108 mL

Therefore the volume occupied is 108 mL