## Logarithms

Emily Oren 3C
Posts: 50
Joined: Fri Sep 29, 2017 7:07 am

### Logarithms

Can someone please explain the sig fig rules for logarithms? And why do they make sense? Why can't we just use the number of sig figs in the given numbers in the question?

Emily Glaser 1F
Posts: 156
Joined: Thu Jul 27, 2017 3:01 am

### Re: Logarithms

If he didn't mention it in class, I wouldn't worry about it.

Priscilla Okaiteye
Posts: 61
Joined: Tue Nov 21, 2017 3:02 am

### Re: Logarithms

You would have to see the number of significant figures in the log(excluding whats beyond the 10^x) and in your answer, that's the number of sig figs to the right of your decimal.

Chem_Mod
Posts: 17547
Joined: Thu Aug 04, 2011 1:53 pm
Has upvoted: 393 times

### Re: Logarithms

When you take the log base 10 of some number (i.e. 2.45 * 102), the answer you get is 0.389166..... To get correct sig figs, you would write 2.389. That is because the # to the left of the decimal arises from the power of 10. if you did log base 10 of 2.45 then it's 0.389.