Waec Model Questions Vol1 2021 Chemistry Question 25

Practice objective / multiple choice question 25 from the 2021 Waec Model Questions Vol1 Chemistry examination.

Waec Model Questions Vol1 2021 Chemistry Objective / Multiple Choice Medium Difficulty
Question 25 WAEC_MODEL_QUESTIONS_VOL1 • 2021 • CHEMISTRY • objective

A 5.00 g sample of a mixture containing CaCO₃ and Na₂CO₃ is heated so that both carbonates decompose: CaCO₃ → CaO + CO₂ and Na₂CO₃ → Na₂O + CO₂. The total volume of CO₂ collected over water at 25 °C and 760 mmHg is 1.68 L. Assuming the overall decomposition yield is 85 % (the same for both carbonates), calculate the mass of CaO obtained (to three significant figures).

Answer Options

A. 0.300 g
Correct Answer B. 0.267 g
C. 0.215 g
D. 0.350 g
Correct Answer
B
Correct Option:
0.267 g

About This Question

This is Waec Model Questions Vol1 2021 Chemistry Question 25. It is a objective / multiple choice question from the 2021 Waec Model Questions Vol1 Chemistry examination.

Difficulty level: Medium .

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