Distilled white vinegar has a pH of 2.4 Water as a Reactant. What is the [H⁺] of distilled white vinegar?

Question

Quizplus · Accepted Answer

The [H⁺] of distilled white vinegar can be calculated using the formula: [H+] = 10^(-pH). So [H+] = 10^(-2.4) = 2.51 x 10^-3 M Since vinegar is a weak acid, it partially dissociates in water to form H+ and acetate ions (CH3COO-). The balanced chemical equation for this reaction is: CH3COOH + H2O ⇌ H3O+ + CH3COO- From the equation, we can see that the [H⁺] is equal to the concentration of undissociated acetic acid (CH3COOH). To calculate the concentration of CH3COOH, we need to use the expression for the acid dissociation constant (Ka) of acetic acid: Ka = [H3O+][CH3COO-]/[CH3COOH] At equilibrium, we can assume that the concentration of CH3COOH that dissociates is negligible compared to the initial concentration, so we can simplify the expression: Ka = [H+][CH3COO-]/[CH3COOH] Rearranging and substituting known values, we get: [CH3COOH] = [H+][CH3COOH]/Ka [CH3COOH] = (2.51 x 10^-3 M)(0.1 M)/1.8 x 10^-5 [CH3COOH] = 1.39 x 10^-1 M Therefore, the [H⁺] of distilled white vinegar is 1.39 x 10^-1 M. Choice C is the only option that matches this value.

Distilled White Vinegar Has a PH of 2