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4 years ago

11. The Ka for benzoic acid is 6.5 × 10–5. Calculate the pH of a 0.10 M benzoic acid solution.

Chemistry

1 answer:

Lisa [10]4 years ago

4 0

Answer:

2.6

Explanation:

Benzoic acid is a weak acid that dissociates according to the following equation.

C₆H₅COOH(aq) ⇄ C₆H₅COO⁻(aq) + H⁺(aq)

We can calculate the equilibrium concentration of H⁺ using the following expression.

[H⁺] = √(Ka × Ca)

where,

Ka is the acid dissociation constant

Ca is the initial concentration of the acid

[H⁺] = √(6.5 × 10⁻⁵ × 0.10) = 2.5 × 10⁻³

The pH is

pH = -log [H⁺] = - log 2.5 × 10⁻³ = 2.6

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Answer:

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Answer:

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Explanation:

Hello,

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