Sig Figs for logarithmic funcitons

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Gabriella Bates 2L
Posts: 94
Joined: Thu Jul 11, 2019 12:15 am

Sig Figs for logarithmic funcitons

Postby Gabriella Bates 2L » Sun Dec 01, 2019 8:42 pm

How do sig figs work on logarithmic functions when doing pH calculations?

zachary_nhem_4I
Posts: 57
Joined: Sat Aug 17, 2019 12:18 am

Re: Sig Figs for logarithmic funcitons

Postby zachary_nhem_4I » Sun Dec 01, 2019 10:36 pm

I'm sure the number of sig figs would be the same as the concentration that is given

Mitchell Koss 4G
Posts: 109
Joined: Sat Jul 20, 2019 12:17 am

Re: Sig Figs for logarithmic funcitons

Postby Mitchell Koss 4G » Mon Dec 02, 2019 6:33 pm

Sig fig rules are standard for any kind of problem

Sebastian Lee 1L
Posts: 134
Joined: Fri Aug 09, 2019 12:15 am
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Re: Sig Figs for logarithmic funcitons

Postby Sebastian Lee 1L » Tue Dec 03, 2019 10:31 am

Actually, the sig figs for pH are a little different than normal. Essentially, if you are calculating the pH from a given concentration, the number of sig figs in the concentration is the number of sig figs you put AFTER the decimal point in the pH.

For example, if I was given a 3.14 * 10-2 M solution of HCl, I would find the pH to be 1.503. This is because the concentration has 3 sig figs so I would need 3 digits AFTER the decimal point on my pH. The 1 in front of the decimal does not count.

Michelle Le 1J
Posts: 50
Joined: Fri Aug 09, 2019 12:16 am

Re: Sig Figs for logarithmic funcitons

Postby Michelle Le 1J » Tue Dec 03, 2019 10:35 am

When you get the concentration and are trying to solve the pH, you would count how many sig figs the concentration has so for your answer, that would be the amount of numbers after the decimal point in your pH.

005321227
Posts: 90
Joined: Sat Sep 07, 2019 12:15 am

Re: Sig Figs for logarithmic funcitons

Postby 005321227 » Sat Dec 07, 2019 9:48 pm

count the sig figs AFTER your decimal :)

rohun2H
Posts: 85
Joined: Wed Sep 18, 2019 12:19 am

Re: Sig Figs for logarithmic funcitons

Postby rohun2H » Sat Dec 07, 2019 10:17 pm

I believe sig figs are also counted after the decimal when provided a pH and you are asked to give some numerical number, say a concentration for example. It was briefly mentioned by my TA.


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