NCERT · Class 10 · Science · Acids, Bases and SaltsCalculate the pH of a solution containing 0.1 M HCl and 0.2 M NaOH.

To calculate the pH of the solution, we need to determine the concentration of hydrogen ions (H+) in the solution.

First, we need to calculate the concentration of hydroxide ions (OH-) in the solution using the formula:

[OH-] = [NaOH] = 0.2 M

Next, we can use the formula:

pH + pOH = 14

where pOH is the negative logarithm of the concentration of hydroxide ions (OH-).

Rearranging the formula to solve for pH, we get:

pH = 14 - pOH

Now, we can calculate the pOH using the formula:

pOH = -log[OH-]

Substituting the value of [OH-], we get:

pOH = -log(0.2) = 0.7

Now, we can substitute the value of pOH into the formula for pH:

pH = 14 - 0.7 = 13.3

Therefore, the pH of the solution is 13.3.