How do you calculate the mean of Molarity of the base in an

Solution

Ans. # Step 1: Write the balanced equation of neutralization:

A balanced reaction for titration with monprotic acid can be written as-

                        NaOH(aq) + AH(aq) ------> NaH(aq) + H₂O(aq)

1 mol NaOH neutralizes 1 mol acid (AH).

#Step 2: At the equivalence point, moles of H⁺ produced by acid must be equal to the moles of OH^- produced by the base.

That is-           x(M1V1), acid = y(M2V2), base

            Where, x = moles of H⁺ produced per mol acid

                        y = moles of OH^- produced per mol base.

Since type of acid is NOT mentioned, it can be monoprotic, diprotic or triprotic, so let number of moles of H⁺ given by 1 mol acid be x. NaOH is monobasic, so, y = 1.

            Or, x(M1V1), acid = (M2V2), NaOH

            Or, M2 = x(M1V1) / V2

In the above expression, all the quantities except M2 are known during the experiment.

So, molarity of NaOH, M2 can be calculated.

# Step 3: Calculation of Average Molarity: Calculate molarities of NaOH in all the trials.

Average molarity = (sum of molarities in all trials) / Number of trials

For example, if you have 3 trials-

            Average molarity = (M2,_{trial 1} + M2,_{trials 2} + M3,_{trial 3}) / 3