# Problem: Potassium sorbate, KC6H7O2 (molar mass 150 g/mol) is commonly added to diet soft drinks as a preservative. A stock solution of KC6H7O2(aq) of known concentration must be prepared. A student titrates 45.00 mL of the stock solution with 1.25 M HCl(aq) using both an indicator and a pH meter. The value of Ka for sorbic acid, HC6H7O2, is 1.7 x 10-5.(a) Write the net ionic equation for the reaction between KC 6H7O2(aq) and HCl(aq).

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###### FREE Expert Solution

We are asked to determine the concentration of a stock solution of sorbic acid HC6H7O2 by first writing its net ionic reaction with HCl

Part A: Writing the net ionic equation

• Potassium sorbate, KC6H7O2 is an ionic compound which will dissociate into ions when in a solution:

• Potassium K is from group 1A and will have +1 charge → K+

• Sorbate is the deprotonated form of sorbic acid → C6H7O2-

• The dissociation of KC6H7O2 is:

KC6H7O2(aq) → K+(aq) + C6H7O2-(aq)

86% (171 ratings)
###### Problem Details

Potassium sorbate, KC6H7O2 (molar mass 150 g/mol) is commonly added to diet soft drinks as a preservative. A stock solution of KC6H7O2(aq) of known concentration must be prepared. A student titrates 45.00 mL of the stock solution with 1.25 M HCl(aq) using both an indicator and a pH meter. The value of Ka for sorbic acid, HC6H7O2, is 1.7 x 10-5.

(a) Write the net ionic equation for the reaction between KC 6H7O2(aq) and HCl(aq).