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Acids, bases and titration — Question 131

Original QCE Vault practice · 4 marks

Q131 · Practice questionSimple familiar4 marks

QUESTION 131 (4 marks)

Solution X is 0.00500 mol L⁻¹ HCl with pH 2.30. Solution Y is 0.0500 mol L⁻¹ of a weak monoprotic acid with pH 3.30. Both are at the same temperature.

(a) Compare the initial acid concentrations and the hydrogen-ion concentrations of X and Y. [2 marks]

(b) Explain why X can have the lower pH despite its lower initial acid concentration. [2 marks]

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