How would the pKa of the unknown acid be affected (higher, lower, or no change)

Question

How would the pKa of the unknown acid be affected (higher, lower, or no change) if the following errors occurred? Please explain.

a) The pH meter was incorrectly calibrated to read lower than the actual pH.
b) During the titration several drops of NaOH missed the reaction beaker and fell onto the bench top.
c) Acid was dissolved in 75 mL of distilled water rather than 50 mL of distilled water.

Also, the same question, but if it says: How would the molar mass of the unknown acid be affected (higher, lower, or no change) if the following errors occurred? Please explain.

Same things that are asked in part a,b, and c.

Explanation / Answer

(Lower the pKa , greater is the acidity greater H +, i.e, lower the pH value)*

a. pKa will be lower than expected . molar mass will remain constant

b. pka will be lower than expected.( normality of acid higher , pH lower , pKa lower ) more acid will remain in solution. no change in molar mass of acid

c. pka will increase. ( normaility decreases , ph increases, pKa increases. ) molarity of the acid in the given solution will be decreased if it is desolved in 75ml rather than 50ml

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