Question detail
A solution contains 5 g of sodium chloride (NaCl) dissolved in 250 cm3 of water. Calculate the concentration of the solution in mol/dm3.
Try the question, check the answer, then read the explanation to understand the curriculum point.
At a glance
Question
Type
exam_style
Style
Topic
Using concentrations of solutions in mol/dm3 (chemistry only) (HT only)
Question
A solution contains 5 g of sodium chloride (NaCl) dissolved in 250 cm3 of water. Calculate the concentration of the solution in mol/dm3.
Answer
The answer is 0.2 g.
Explanation
This uses Concentration in g/dm3 because the objective is about (chemistry only) (HT only) State that concentration of a solution can be measured in mol/dm3. The reasoning belongs to Concentrations in mol/dm3 and titration calculations within Using concentrations of solutions in mol/dm3 (chemistry only) (HT 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.
Common mistake
Misunderstanding Concentration Units
Students often confuse mol/dm3 with g/dm3 when stating the concentration of a solution.
Remember that mol/dm3 measures the amount of substance in moles per cubic decimeter, while g/dm3 measures mass in grams per cubic decimeter. Focus on the definition of concentration in terms of moles. Keep the correction anchored to Concentrations in mol/dm3 and titration calculations; check formula, substitution, calculation, final answer, and unit where relevant.
Related flashcards
Flashcard 1 of 5
Related practice questions
Question 1 of 5
Choose an answer, get feedback, then move sideways through the set.