Question

What would happen to the pH if you continued to add acid to the Alka Seltzer?

Answer 1

Acid is initially having low pH value (Depending upon the strength of acid).

Alka Seltzer is an alkaline component.

There will occur a neutralization reaction between acid and Alka Seltzer.

Alka Seltzer is a basic compound with excess HO^- ions and hence pOH less than 7.

Progressive addition of acid to alka seltzer consumes HO^- ions and lowers down concentration.

As pOH = - log[HO^-] = log(1/[HO^-]) with decrease in [HO^-], pOH increases.

Hence on addition of acid to Alka Seltzer pOH increases. and pH decreases.

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