Friday

August 1, 2014

August 1, 2014

Posted by **Jay** on Friday, March 2, 2007 at 10:07am.

Add the partial pressures of the air and that of the vaporized helium.

120 mL of LHe has a mass of 0.147 g/ml x 120 mL = 17.64 g. That is = 4.406 moles. From that and the volume and temperature, you can calculate the partial pressure of He, using

P = nRT/V

R = 8.205*10^-2 atm*L/mole K

P(He)= 107.7 atm

The air partial pressure is much less. It starts out at 1.0 atm at 118K and rises to 1.0 x (298/118) = 2.5 atm at the higher temperature of 298 K.

Add the two partical pressures for the total pressure.

I don't guarantee my numbers, so check them yourself. The method should work.

thanks

**Related Questions**

College Chemistry - 1. From data below, calculate the total heat (in J) ...

College Chemistry - 1. From data below, calculate the total heat (in J) ...

College Chemistry - 1. From data below, calculate the total heat (in J) ...

Physics - The boiling point of helium at 1 atm is 4.2 K. What is the volume ...

Physics - Useful Constants: 1 Torr = 133.32 Pa; R = 8.3145 J/mol·K You have a ...

physics - A rigid tank contains 38:0 kg of O2 gas at a pressure of 9:70 atm. If ...

science - 1. the molar mass of helium is 4.00 g/mol. calculate the volume of 1 ...

Physics - The boiling point of the helium at i atm is 4.2 k, what is the volume ...

Chem hw! - 1. What pressure would be needed to compress 25.1 mL of hydrogen at 1...

Chem hw! - 1. What pressure would be needed to compress 25.1 mL of hydrogen at 1...