Waec Model Questions Vol1 2019 Chemistry Question 7

Practice essay / theory question 7 from the 2019 Waec Model Questions Vol1 Chemistry examination. This question covers Acids Bases and Salts .

Waec Model Questions Vol1 2019 Chemistry Essay / Theory

Topic: Acids Bases and Salts

Question 7 WAEC_MODEL_QUESTIONS_VOL1 • 2019 • CHEMISTRY • essay

A 0.200 mol sample of benzoic acid (C₆H₅COOH, Kₐ = 6.3×10⁻⁵) is dissolved in 1.00 L of water and then 0.150 mol of sodium benzoate (C₆H₅COONa) is added. The solution is therefore a buffer of benzoic acid and its conjugate base.

Question Parts

( a )

Calculate the pH of the resulting solution at 25 °C.

( b )

If 0.050 mol of 0.10 M HCl is added to the buffer, calculate the new pH (assume volume change is negligible).

( c )

To restore the original pH, how many millilitres of 0.10 M NaOH must be added? (Assume the total volume remains essentially 1 L.)

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About This Question

This is Waec Model Questions Vol1 2019 Chemistry Question 7. It is one of the essay questions from the 2019 Waec Model Questions Vol1 Chemistry examination.

The question covers Acids Bases and Salts .

View More Waec Model Questions Vol1 2019 Chemistry Questions More Waec Model Questions Vol1 Practice Questions Back to Questions

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