Useful Constants: 1 Torr = 133.32 Pa; R = 8.3145 J/mol·K

You have a thin metal sphere of unknown volume that contains helium gas at low pressure. You put the entire metal sphere into a bath of liquid nitrogen, and a pressure gauge on the sphere indicates a pressure of 288 torr.

Given that the volume of the metal sphere, pressure gauge, etc., was 367 mL, how many moles of helium gas would you have?

temp of liquid nitrogen=77.2K
I used pV=nRT

Which would be 288*367=n*8.3145*77.2

I got n=641.8811 moles

But the answer is wrong can anyone help?

1 answer

anyone????