## Sig figs

Volume: $\Delta S = nR\ln \frac{V_{2}}{V_{1}}$
Temperature: $\Delta S = nC\ln \frac{T_{2}}{T_{1}}$

Steven_Liu_3H
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### Sig figs

How do we deal with sig figs when using ln(T2/T1)?

Chem_Mod
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### Re: Sig figs

For logs and natural logs, usual convention is this:
If the ratio of T2/T1 has x number of sig figs, then the answer to a log or natural log should have x decimal places.

Example: If I had ln(0.5/2.0), the answer to 0.5/2.0 has 1 sig fig thanks to the 0.5. So, when you solve for the natural log, your answer should have 1 decimal place. The proper answer to ln (0.5/2.0) is -1.4.

I hope this helps.

Annie Zhang_ 3C
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Joined: Wed Sep 21, 2016 2:59 pm

### Re: Sig figs

To add to the above, the textbook (6th edition) has notes for how to do sig figs on pages A5 and F10 of the appendix. Specifically, rules for logarithms and exponentials are on page A6 that basically say that the answer should have the same number of sig figs as the original number. Hope that looking for more background explanation in the textbook will also be of help to you!

Camille_2G
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