Question detail

For Using moles to balance equations (HT only), which formula choice answer best supports this Unit 4.3 objective: (HT only) Use mole ratios calculated from masses to balance a symbol equation?

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

Show answer Topic hub Objective page

At a glance

MCQ

Type

practice

Style

Topic

Use of amount of substance in relation to masses of pure substances

Question

A. 20 g/dm³
B. Wrong formula choice: confuses HT only with a nearby Unit 4.3 idea
C. Wrong unit check: uses the wrong unit for Using moles to balance equations (HT only)
D. Wrong calculation link: does not support (HT only) Use mole ratios calculated from masses to balance a symbol equation

Answer

The correct option is 20 g/dm³. The calculated answer is 20 g/dm3.

Explanation

The correct option is 20 g/dm³. This uses Concentration in g/dm3 because the objective is about (HT only) Use mole ratios calculated from masses to balance a symbol equation. This formula choice variant asks students to separate HT only from similar Unit 4.3 calculation steps. The reasoning belongs to Using moles to balance equations (HT only) within Use of amount of substance in relation to masses of pure substances, 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 HT 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 Mass Ratios with Mole Ratios

Students often confuse mass ratios with mole ratios when balancing equations, leading to incorrect calculations.

Always ensure you are using the mole ratios derived from the coefficients of the balanced equation, not the masses of the reactants or products.

Related flashcards

Flashcard 1 of 5

Press Space to flip, arrows to move

For Using moles to balance equations (HT only), which option best supports this Unit 4.3 objective: (HT only) Use mole ratios calculated from masses to balance a symbol equation?