A10-l drum of ether at 18°c is open to the atmosphere {p = 760 torr) and contains 6 l of liquid. the top is sealed and the drum dented so that it now has an 8-l capacity. if the vapor pressure of ether at 18°c is 400 tort, what is the pressure inside the dented, sealed drum?

the final  pressure = 1120 torr

Explanation:

In the starting, when a 10-L drum consist 6 L of ether at 18°C

Volume of gas  

Total pressure of gas which is equal to Atmospheric Pressure = 760 Torr

vapor pressure of liquid (ether) = 400 Torr

vapor pressure of air

when the drum top is sealed & dented to 8 L capacity

Volume of gas

Total pressure of gasses

vapor pressure of ether  

vapor pressure of air

But some of the liquid (ether) vapor will condensed into liquid just to maintain the vapor pressure of ether at 400 Torr )

therefore, the final  pressure

final total pressure is 1120 torr

Explanation:

given data

volume v1 = 10 L

volume v2 = 6 L

temperature = 18°C

atmosphere pressure P = 760 torr

volume v3 = 8 L

vapor pressure = 400 torr

to find out

pressure inside the dented

solution

we know here at 6 L volume by small amount of vaporize no temperature will change

and

gas volume in drum is = 10 - 6 = 4L

and

atmosphere pressure = total pressure inside drum

and

partial pressure of air is = 760 - 400

partial pressure of air is  = 360 torr  

so

at 8 L volume sealed and sealed then gas volume inside drum is

gas inside = 760 ×

gas inside = 1560 torr

so partial pressure either side is

partial pressure = 2× 400  = 800 torr

partial pressure = 2× 360 = 720 torr

so we keep vapor pressure here 400 torr

so

final total pressure = 400 + 720

final total pressure is 1120 torr