Question detail

For Atom economy, which unit conversion answer best supports this Unit 4.3 objective: (chemistry only) Use ratios, fractions and percentages in atom-economy calculations. (MS 1c)?

Try the question, check the answer, then read the explanation to understand the curriculum point.

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At a glance

MCQ

Type

practice

Style

Topic

Yield and atom economy of chemical reactions (chemistry only)

Question

A. 33.3%
B. Wrong unit conversion: confuses chemistry only with a nearby Unit 4.3 idea
C. Wrong unit check: uses the wrong unit for Atom economy
D. Wrong calculation link: does not support (chemistry only) Use ratios, fractions and percentages in atom-economy calculations. (MS 1c)

Answer

The correct option is 33.3%. The calculated answer is 33.3 %.

Explanation

The correct option is 33.3%. This uses Percentage Yield because the objective is about (chemistry only) Use ratios, fractions and percentages in atom-economy calculations. (MS 1c). This unit conversion variant asks students to separate chemistry only from similar Unit 4.3 calculation steps. The reasoning belongs to Atom economy within Yield and atom economy of chemical reactions (chemistry only), so it should not be confused with nearby quantitative ideas such as mass, moles, concentration, yield, atom economy, or gas volume unless those are named in the objective. Use the focus term chemistry only to keep the answer aligned with AQA GCSE Chemistry 8462 Unit 4.3. The other options are weaker because they either use the wrong formula, the wrong unit, a vague relationship, or the wrong quantitative context.

Common mistake

Confusing Ratios with Percentages

Students often confuse how to use ratios and percentages in atom-economy calculations, leading to incorrect answers.

To fix this, students should practice converting ratios to percentages by dividing the part by the whole and multiplying by 100, ensuring they understand the difference between the two concepts. Keep the correction anchored to Atom economy; check formula, substitution, calculation, final answer, and unit where relevant.

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For Atom economy, which option best supports this Unit 4.3 objective: (chemistry only) Use ratios, fractions and percentages in atom-economy calculations. (MS 1c)?