Suppose you performed an exeriment, but forgot to standardize the pH meter. As a result of...

Suppose you performed an exeriment, but forgot to standardize the pH meter. As a result of this oversight, all of the pH readings were incorrectly high. Would your experimentally determined pKa for the solution be incorrectly high, incorrectly low, or unaffected? Explain your answer.

Note: pH = pKa + log([conjugate base] / [acid])

Solutions

Expert Solution

We know that pH is a negative logarithm of [H3O+] and pKa is the negative logarithm of Ka;

According to Henderson Hasselbach equation:

pH= pKa + log([conjugate base]/[acid]) , this equation is used to calculate the pH of the buffer solution.

When we accidently report the pH reading high then it will surely affect the calculation of pKa. This is because pKa is equal to pH at half equivalence point(The point at which the concentration of an added base is equal to the half of the original concentration of acid).

Thus, if the reading of pH is high then we will get the reading of pKa also high. So, pH high reading makes the reading of pKa incorrectly high.

queen_honey_blossom answered 2 years ago

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