# Ideal gas and absolute zero

1. Feb 14, 2010

### hover

1. The problem statement, all variables and given/known data
Calculate your experimental value of absolute zero , how does your experimental value compare to the theoretical value -273C?

2. Relevant equations
T_abs=(S1*T2-S2*T1)/(S1-S2)

3. The attempt at a solution

This is all part of a lab. I'm not asking people to do any calculations. I'm more worried about my calculations from what I got and I'm pretty sure I did them correctly. The accepted value for absolute zero is -273C. The value I got when calculating was -72.18 C. My question is can air be treated as an ideal gas so that the calculation on absolute zero is possible? If air can't be treated as an ideal gas then it would explain the huge difference in my value vs the accepted value.

Thanks!

2. Feb 14, 2010

### ideasrule

The ideal gas approximation is VERY good for air near room temperature. I'd say it's extremely accurate up to at least -100 degrees Celsius.

3. Feb 14, 2010

### hover

So that means I did something wrong right?

4. Feb 14, 2010

### ideasrule

Yes, I'd say so. You should be able to get a reasonable value (within 50 degrees or so of the actual answer).

5. Feb 14, 2010

### hover

ok. thanks for letting me know