Waec Model Questions Vol1 2021 Chemistry Question 7

Practice essay / theory question 7 from the 2021 Waec Model Questions Vol1 Chemistry examination. This question covers Acids, Bases and Salts .

Waec Model Questions Vol1 2021 Chemistry Essay / Theory

Topic: Acids, Bases and Salts

Question 7 WAEC_MODEL_QUESTIONS_VOL1 • 2021 • CHEMISTRY • essay

A 0.250 mol sample of sodium carbonate (Na2CO3) is dissolved in 500.0 mL of water. The solution is then titrated with 0.1000 M hydrochloric acid (HCl) until the pH reaches 8.0. The carbonate ion undergoes successive neutralisation reactions with H+ ions.

Question Parts

( a )

Write the net ionic equation for each step of the neutralisation of carbonate ion by HCl.

( b )

Calculate the volume (in mL) of 0.1000 M HCl required to reach a pH of 8.0. Use Ka2 of carbonic acid = 4.8 × 10⁻¹¹.

( c )

Explain why the pH at the first equivalence point of this titration is greater than 7.

Detailed Solution & Marking Scheme

Get the step-by-step solution, key points required by examiners and detailed marking guidance through the Edcrib AI Tutor.

Reveal Answer

About This Question

This is Waec Model Questions Vol1 2021 Chemistry Question 7. It is one of the essay questions from the 2021 Waec Model Questions Vol1 Chemistry examination.

The question covers Acids, Bases and Salts .

View More Waec Model Questions Vol1 2021 Chemistry Questions More Waec Model Questions Vol1 Practice Questions Back to Questions

Master the Exam!

You've seen a preview, but there are thousands more questions plus AI tutor to break down complex solutions.

Unlock Full Access Available for Android & Windows

Chat with Support