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Acids, bases and titration — Question 85

Original QCE Vault practice · 5 marks

Q85 · Practice questionComplex familiar5 marks

QUESTION 85 (5 marks)

A 20.00 mL sample of an unknown weak monoprotic acid requires 15.00 mL of 0.1200 mol L⁻¹ NaOH. The untreated acid has pH 2.80.

a) Calculate its initial analytical concentration. [2 marks]

b) Calculate Ka using the measured pH and allowing for dissociation. [3 marks]

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