Question

If the hydrogen ion concentration is 10-7M, what is the pH of the solution?

Show all work.

Answer 1

\(\large pH = -log[H^+]\)

Answer 2

I understand that much, but don't know where to plug the numbers in.

Answer 3

Well your \(\large [H^+]\) is the hydrogen ion concentration.
I'm not sure if the one given in your question is correct. Should it be \(\sf 10*10^{-7}~?\)

Answer 4

That's all the question says is 10 to the negative 7th power.

Answer 5

Just \(\Large 10^{-7}M\) ??

Answer 6

Yes

Answer 7

Oke then plug that in the formula \(\large pH = -log[H^+]\)

Answer 8

So \(\large pH = -log[10^{-7}]\)

Answer 9

I'm totally lost with this question lol

Answer 10

Where are you lost? the only thing you have to do is calculate \(\large -log[10^{-7}]\)

Answer 11

what does -log equal though?

Answer 12

log is a function on your calculator. just put a - in front
So enter: -log(10^-7)

Answer 13

I don't have a calculator.

Answer 14

Then go to www.google.com and enter -log(10^-7)

Answer 15

google has a calculator

Answer 16

One minute.

Answer 17

answer of 7?

Answer 18

so pH = 7?

Answer 19

yes that is correct :)

Answer 20

thank you!

Answer 21

No problem :)

Answer 22

pH of 10^-7 M HCl = 7
then the pH of 10^-8 M HCl comes out to be 8.

which is wrong.

think of it this way.
you added small amount of acid into water, and still the solution remained neutral or turned basic if conc of acid = 10^-8??
adding an acid can never make water basic or neutral.

use this link to teach yourself as to how to proceed for the solution to this question, and if you face any difficulty, just ask.
http://www.faculty.umassd.edu/michele.mandrioli/172cbook/fCHM2.D.2.html