What is the correct solution for the temperature expansion problem?

AI Thread Summary
The discussion centers on a temperature expansion problem involving a steel container filled with alcohol, where the goal is to determine the temperature increase needed to raise the pressure by 6 bar. The initial calculation yielded a temperature change of 0.97K, but the expected answer is 9.7K. Participants suggest that the discrepancy may stem from a factor of ten error, possibly related to the conversion of compressibility units. The method used for solving the problem is confirmed to be correct, indicating that the issue lies in the input values or potential typos in the reference material. Clarifying these points is essential for reaching the correct solution.
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Homework Statement


A steel container is filled with alcohol. For how much kelvins we have to raise the temperature for the pressure to be raised by 6 bar?
Compressibility of alcohol is
<br /> \kappa=1.15 \cdot 10^{-4} bar^{-1}<br />
temperature coefficient of volume expansion of alcohol is
<br /> \beta_a= 7.5 \cdot 10^{-4} K^{-1}<br />
temperature coefficient of length expansion of steel is
<br /> \alpha_s= 1.2 \cdot 10^{-5} K^{-1}<br />

Homework Equations


Look at attempt at solution.

The Attempt at a Solution


I solved this problem like this:
<br /> \frac{\Delta V}{V}=(\beta_a-3\alpha)\Delta T\\<br /> \frac{\Delta V}{V}=\kappa\Delta p\\<br /> \frac{\kappa\Delta p}{\beta_a-3\alpha}=\Delta T= 0.97K\\<br />
But the solution is wrong. The correct answer is 9.7K. I'm interested where I made a mistake.
 
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It looks like your answer is off by a factor of 10. This may be due to a typo or an error in the conversion of compressibility units to bar-1.
 
I checked and get 0.97K. Do you think the solving process is correct?
 
The method is correct. If you are certain that the input numbers are also correct, then the answer in the back of the book may be a typo.
 
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