Hi,
I'm trying to solve some chemistry problems, like the ones my teacher says will appear on our exams.
The problem reads like this:
What is the hydrogen conentration in a bleach sample that register 9.55 using a pH meter?
My Attempt:
Since this sample register a 9.55 on a pH meter,it occurs to me that this sample is basic, and I can use the formula:
pOH = -log (H^+), to solve for (OH^-)
=-log(9.55)
=-0.980
From here I thought,maybe if I substitute that result into the equation pH + pOH = 14, I might arrive at the answer I'm looking for; which is 0 000 000 000 35 M.
pH + 0.980 = 14
pH = 13.02
Evidently I took the wrong approach.
Can you help me with this problem?
Have a Great Night
i did not exactly get that answer... but i still think this will helps. i did 10^pH formula. i got 2.818 x 10^-10 as my naswer. i toke that and divided it by the molar mass of blaech. i got the answer 3.78 x 10^12... which is simalr to your answer
I think you are trying to make this far more difficult that it is. Also, I think your prof gave you the wrong answer (or you've state something wrong or copied something wrong).
if pH = 9.55, then
pH = -log(H^+)
9.55 = -log)H^+)
-9.55 = log(H^+)
(H^+) = 2.82E-9M
(the OH^- is 3.5E-5M
(You should know your answer of pH = 13.02 isn't right. the PROBLEM states pH = 9.55 and not 13.02.
By the way, pOH = -log(OH^-), not what you wrote above.
And my problem is I can't read my calculator. For pH = 9.55, (H^+) = 2.82E-10.
I submitted an incorrect answer to that problem. The correct answer is 0.000 000 000 28 M. I apolgise.
I've been sleep deprived.
So the answer 2.8E-10 is correct. I should have rounded that last two out of the number and didn't.
Of course, I can help you solve this problem!
To find the hydrogen concentration in a bleach sample, we need to use the pH value obtained from a pH meter. The pH value measures how acidic or basic a solution is, with low values being acidic and high values being basic.
You were correct in using the formula pOH = -log(OH^-) to find the hydroxide concentration. However, it seems there was a mistake in your calculations. Let's correct it:
pOH = -log(9.55)
pOH ≈ 0.02
Now, to find the hydrogen concentration (H+), we can use the equation pH + pOH = 14. Let's substitute the pOH value we found:
pH + 0.02 = 14
pH ≈ 13.98
The pH value of 13.98 indicates that the bleach sample is highly basic. However, this is not the hydrogen concentration; it is the negative logarithm of the hydrogen concentration (H+). To find the hydrogen concentration (H+), we need to take the antilog (10^x) of the pH value:
H+ ≈ 10^(-pH)
H+ ≈ 10^(-13.98)
H+ ≈ 1.26 x 10^(-14) M
So, the hydrogen concentration in the bleach sample is approximately 1.26 x 10^(-14) M.
In summary, the correct approach to solve this problem involves finding the pOH using the formula pOH = -log(OH^-), then using the equation pH + pOH = 14 to find the pH value, and finally taking the antilog of the pH value to obtain the hydrogen concentration (H+).
If you have any further questions or need additional clarification, feel free to ask!