WAEC 2024 Chemistry · Question 35
Consider the reaction represented by the equation: C 3 H 8 + 5 O 2 → 3CO 2 + 4H 2 O If 0.1 mole of C 3 H 8 was…
Question
Consider the reaction represented by the equation: CH + 5 O → 3CO + 4HO If 0.1 mole of CH was completely burnt, what volume of CO would be produced at stp? [volume of gas at stp = 22.4dmmol].
- A.6.72dm
- B.2.24dm
- C.0.30 dm
- D.0.10dm
Answer: A. 6.72dm
Explanation written with AI and checked against the answer key
Step 1: Analyze the question We are given 0.1 mole of propane (C₃H₈) burnt completely. We need the volume of CO₂ produced at stp. Step 2: Concept The balanced equation gives mole ratios. At stp, 1 mole of any gas occupies 22.4 dm³: Volume = moles × 22.4 dm³/mol Step 3: Solution From the equation: C₃H₈ + 5O₂ → 3CO₂ + 4H₂O 1 mole of C₃H₈ produces 3 moles of CO₂. So 0.1 mole of C₃H₈ produces: 0.1 × 3 = 0.3 mole of CO₂ Volume of CO₂ = 0.3 × 22.4 = 6.72 dm³ Step 4: Answer The correct option is A. 6.72 dm³. Note that option C (0.30 dm³) is a trap. It is the number of moles of CO₂, not the volume. Always multiply by 22.4 to convert moles to volume. Tip: For gas-volume questions, follow this chain: moles given → mole ratio from the equation → moles wanted → × 22.4 dm³. Check that your final answer is in volume units, not moles.AI can make mistakes. Report anything that looks wrong.
Past questions © the examination body (JAMB/WAEC/NECO). DeeepSolve is not affiliated with them. Rights holders: see /copyright.