Question

What is the pH of water at a certain temperature if the value of the ionic product of water is 9.55x10^-4?

a) pH 2.02
b) pH 3.02
c) pH 4.02
d) pH 5.02

Answer 1

The pH of water when the ionic product of water (Kw) is 9.55x10^-4 is found using the formula pH = -log [H3O+], and the correct answer is a) pH 2.02.

Step-by-step explanation:

To calculate the pH of water at a certain temperature when the ionic product of water (Kw) is given as 9.55x10-4, we would use the expression pH = -log [H3O+]. However, to do this, we first need the concentration of hydronium ions [H3O+], which is the square root of Kw since [H3O+] = [OH-] in pure water.

In this case:
[H3O+] = √(9.55 x 10-4)
After calculating the square root, we would then take the negative log of the hydronium ion concentration to find the pH.

Using the provided information as a reference, where pH = -log(9.8 x 10-3) equals to 2.01, we can infer that the concentration of hydronium ion in this problem is higher given the higher Kw. This would lead to a pH that is lower than in the reference, suggesting the correct answer is a) pH 2.02.