Calculate the ph of 1.0 l of the original buffer upon addition of 0.010 mol of solid naoh to the original buffer solution.

This is an incomplete question, here is a complete question.

Consider a buffer solution that is 0.50 M in NH₃ and 0.20 M in NH₄Cl. For ammonia, pKb = 4.75.

Calculate the pH of 1.0 L of the original buffer upon addition of 0.010 mol of solid NaOH to the original buffer solution.

Answer : The pH of solution is, 9.68

Explanation : Given,

Concentration of NH₃ (base) = 0.50 M

Concentration of NH₄Cl (salt) = 0.20 M

Concentration of NaOH =

After addition of NaOH:

Concentration of NH₃ (base) = 0.50 + 0.01 = 0.51 M

Concentration of NH₄Cl (salt) = 0.20 - 0.01 = 0.19 M

First we have to calculate the value of pOH.

Using Henderson Hesselbach equation :

Now put all the given values in this expression, we get:

Now we have to calculate the pH.

Therefore, the pH of solution is, 9.68

14 days is the half-life of phosphorus-32