1. Chemists define pH as "the negative logarithm of the concentration of protons". In mathematical terms:
pH = - log [H+]
What is the pH of a solution whose [H+] is 0.0007 M?
i got it as 7.0 i know it is wrong
2. What is the [H+] in a solution having a pOH of 6 ?
isn't it supposed to add to 14? so 8? but it didn't work
a.
pH = -log(H^+)
pH = -log(7E-4)
pH = -(-3.15)
pH = 3.15
b.
pH + pOH = pKw = 14
pH + 6 = 14
pH = 8
The problems asks for (H^+); therefore,
pH = -log(H^+)
8 = -log(H^+)
-8 = log(H^+)
(H^+) = 1E-8
To find the pH of a solution, you can use the formula pH = -log[H+]. Let's use this formula to solve the first question.
1. Find the pH of a solution whose [H+] is 0.0007 M:
pH = -log(0.0007)
To calculate this, you can use a scientific calculator. Enter 0.0007, then hit the log button (usually denoted as "log" or sometimes "ln"). Finally, multiply the result by -1 to get the pH value.
The correct answer is pH ≈ 3.15, not 7.0.
Now, let's move on to the second question.
2. Find the [H+] in a solution with a pOH of 6:
The pH and pOH values in a solution always add up to 14. So, if the pOH is given as 6, we can find the pH by subtracting 6 from 14:
pH = 14 - pOH
pH = 14 - 6
pH = 8
Therefore, the correct pH value is pH = 8, not 14.