Concentration Worked Example
Part of Moles & Calculations — GCSE Chemistry
This worked example covers Concentration Worked Example within Moles & Calculations for GCSE Chemistry. Revise Moles & Calculations in Quantitative Chemistry for GCSE Chemistry with 22 exam-style questions and 20 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 14 of 17 in this topic. Treat this as a marking guide for what examiners are looking for, not just a fact list.
Topic position
Section 14 of 17
Practice
22 questions
Recall
20 flashcards
🧮 Concentration Worked Example
Concentration measures how many moles of solute are dissolved in 1 dm³ of solution:
Question: 0.25 mol of NaOH is dissolved in 500 cm³ of water. Calculate the concentration in mol/dm³.
500 cm³ ÷ 1000 = 0.5 dm³
c = n ÷ V = 0.25 ÷ 0.5 = 0.5 mol/dm³
Answer: 0.5 mol/dm³
Always convert cm³ to dm³ first by dividing by 1000. Forgetting this step is the most common mistake in concentration calculations.