Yields, atom economy and experimental errors

Yields, atom economy and experimental errors Quiz

Edexcel A-Level Chemistry: Quiz

Studying this course? Keep your progress in one place.

Pick an answer for each. Quizzes never use energy.

5 questions, one answer each

Each answer is checked as you go, with why.

See all 5 questions

  1. 1. A pipette delivers 25.0 cm³ with an uncertainty of ±0.06 cm³. What is the percentage uncertainty?

    • A. 0.060%
    • B. 0.24%
    • C. 0.12%
    • D. 2.4%

  2. 2. A reaction should give 10.0 g of product but 8.0 g is obtained. What is the percentage yield?

    • A. 125%
    • B. 20%
    • C. 80%
    • D. 8.0%

  3. 3. What is the percentage atom economy for making CaO from CaCO₃ → CaO + CO₂ (M: CaCO₃ 100.1, CaO 56.1, CO₂ 44.0)?

    • A. 44.0%
    • B. 100%
    • C. 78.5%
    • D. 56.0%

  4. 4. Which is a systematic error?

    • A. Random variation in judging the end-point
    • B. Using a burette tap that leaks
    • C. A balance that always reads 0.05 g too high
    • D. Parallax in reading a measuring cylinder

  5. 5. Which precaution is most suitable for handling 2.0 mol dm⁻³ hydrochloric acid, an irritant?

    • A. Wear eye protection
    • B. Wear a gas mask
    • C. Warm it before use
    • D. Use a sealed container

Quiz