How do i use the inverse log operation on the TI-84

The problem is simple. You're trying to get an [H+] concentration which is obviously going to have a value of some number times ten raised to a negative power. Therefore, you have to insert the negative value of the pH into the 10^(x). When you insert said negative number you will come out with the right answer.
i.e.
The pH of a sample of human blood was calculated to be 7.41. What is the [H+] concentration of the blood?
10^(-7.41) = [H+]
[H+] = 3.9 E-8  
(the answer should only have two sig. figs because the pH has two digits after the decimal.

Okay, I've finally got this. Haha I've spent an hour messing around with my calculator & I'm pretty sure I know the answer.

If you have a TI-84, Press the 2ND button and the LOG button after (this will give you a small 10^( on the screen) and insert the ion concentration (for chem). You should get the answer that way.

So it would look like this:
10^(12.40)
2.51188...

If I understand you correctly, the inverse of the log operation is exponentiation. So if your log = x, the inverse is 10 raised to the x power. On most TI calculators this is on the same key as the log function.

michael

Dude it's simple.
given something like [h30]=1.5x10^-3

- button, log button, 1.5 then shift button, log button (to get the 10x) then, the - button (if your integer is negative, then 3 then two parentheses.

so it looks like this:
-LOG(1.5 10^(-3))
answer should be 2.82 if not then you did something wrong.

Try this: (log(V)^(-1), and if that don't work, I'm stumped. :(

GIVEN [H] =3.8X10^-4 WHATS THE PH & POH &OH