More Mathematical Problems on pH


 Hello fam! Welcome to today’s class, we are continuing along the path that we started a few days ago. We have been looking at different problems that have to do with the pH and today we shall look at some more problems.


Example 3;

A solution has a pOH of 6.50 at 50oC. What is the pH of the solution?


Solution;

We know that;

pH + pOH = 14

pH = 14 – 6.50

pH = 7.5


Example 4;

Calculate the pH and pOH of 0.02 M H2SO4.


Solution;

We know that we would first find pH because it is an acid;

pH = -log(0.02 M)

pH = 1.69

pOH = 14 – 1.69

=12.31


Example 5;

Calculate the pH and pOH of a solution of 3 * 10^-2 M


Solution;

We know that we would first find pOH because it is an base;

pOH = -log(3 * 10^-2)

= 1.5

pH = 14 – 1.5

= 12.5

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