pH sig figs

[Stacey Phan 2I]

Does pH contribute to sig figs? If so, is it based on after the decimal? For example, does pH=7.834 have 3 or 4 sig figs?

[SainehaMaddineni_3I]

It is based on what's after the decimal when given a pH value. So, in this case, there are 3 sig figs.

[Stuti Pradhan 2J]

You want the least number of sig figs in the problem to match the number of sig figs in your answer. The only thing to look out for is that if you take the log of anything, the answer of the log should have the same number of decimal places as the H+ or OH- concentration does. For example, a H+ concentration of 0.0036 has 2 sig figs. However, the pH would be 2.44 with three sig figs because it has the same number of decimal places as the sig figs in the H+ concentration.

pH=7.834 has 4 sig figs, but the original H+ concentration that was inputted into the log would have only had 3 sig figs.

An explanation for why this is can be found of Dr. Lavelle's website.

Hope this helps!

[Luveia Pangilinan 1A]

I am pretty sure the sig figs will work the same as how we've always done it in this class. Whatever is the least amount of sig figs within a given problem that is what you'll follow for your final answer.

[jasmineculilap_3F]

It would have 4 SFs since we're following the same SF rules. One thing to remember though is that when taking the -log of a number, the total SFs of that number will be the number of SFs in the decimal place. In the case of pH = 7.834, for the -log(#), the # would have had 3 SFs that made 7.834 have 3 SFs in the decimal places.