## Sig Figs in 6B3

AnnikaMittelhauser4E
Posts: 50
Joined: Fri Aug 30, 2019 12:18 am

### Sig Figs in 6B3

6B3 says "A careless laboratory technician wants to prepare 200.0 mL of a 0.025 M HCl(aq) solution but uses a volumetric flask of volume 250.0 mL by mistake. (a) What would the pH of the desired solution have been? (b) What will be the actual pH of the solution as prepared?"

The textbook says the answer for A is 1.6, but shouldn't 1.60 be the correct amount of significant figures? It is just -log(0.025), and 0.025 has two significant figures, which I thought meant the answer needed two digits to the right of the decimal point.

I ran into the same confusion with part B as well. Answer listed as 1.7 when I thought it should be 1.70

WesleyWu_1C
Posts: 93
Joined: Thu Jul 25, 2019 12:16 am

### Re: Sig Figs in 6B3

Yeah, I also believe the answers should be 1.60 and 1.70.

Maya Pakulski 1D
Posts: 83
Joined: Thu Jul 11, 2019 12:17 am

### Re: Sig Figs in 6B3

When looking at pH and pOH there are different significant figure rules, here's a website that explains what they are. http://abacus.bates.edu/acad/depts/biobook/How-SigF.pdf

Siya Shah 1J
Posts: 50
Joined: Sat Aug 17, 2019 12:15 am

### Re: Sig Figs in 6B3

Likely the two sig figs comes from the value of concentration 0.025 M.

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