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Acids, bases and titration — Question 42

Original QCE Vault practice · 5 marks

Q42 · Practice questionComplex familiar5 marks

QUESTION 42 (5 marks)

A weak base B has Kb=4.0×10−5 at 25∘C.

a) Write its reaction with water, including its conjugate acid. [1 marks]

b) Calculate the pH of a 0.10 mol L⁻¹ solution. You may use the small-ionisation approximation. [3 marks]

c) Calculate the Ka of its conjugate acid. [1 marks]

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