(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Imagine that 9.9 g of liquid helium, initially at 4.20 K, evaporate into an empty balloon that is kept at 1.00-atm pressure. What is the volume of the ballonat the following?

(a) 23.0 K

(b) 299 K

2. Relevant equations

PV=nRT

3. The attempt at a solution

I converted th 9.9g of Helium to number of moles. n=2.473mol

and used that to find the volume at T=23 and T=299, but it isn't right.

steps

1) n=9.9g=(9.9g/(4.003g/mol))=2.47314 mol

R=8.314472 <-- gas constant

P= 1 as stated in the problem

V@ T=23 : V=(nRT)/P -> (2.47314*8.314472*23)/1 --> V=472.9466 L

V@ T=299 : V=(nRT)/P -> (2.47314*8.314472*299)/1 --> V=6148.30591237 L

I'm guessing I need to do something with T=4.2 first, but I'm not sure what.

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# Homework Help: Volume of a Balloon

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