Question detail
What happens when aqueous iron(III) ions are treated with sodium hydroxide?
Try the question, check the answer, then read the explanation to understand the curriculum point.
At a glance
MCQ
Type
practice
Style
Topic
Reactions of ions in aqueous solution (A-level only)
Question
- A. A brown precipitate forms
- B. A yellow precipitate forms
- C. A blue precipitate forms
- D. No precipitate forms
Answer
A brown precipitate forms
Explanation
The correct option is A brown precipitate forms. A brown precipitate forms is the best answer because it directly supports the AQA A-Level Chemistry objective to describe reactions of aqueous metal ions with sodium hydroxide. This reasoning is anchored to Aqueous ion tests (A-level only) in Reactions of ions in aqueous solution (A-level only), and it separates reactions from similar A-Level ideas rather than relying on a vague recall statement. Other options are weaker if they use the wrong evidence, calculation, mechanism, observation, unit, or conclusion for this subtopic.
Common mistake
Misidentifying Precipitate Colors
Students often incorrectly describe the color of the precipitate formed when aqueous metal ions react with sodium hydroxide, confusing different metal ions.
To accurately describe the color of the precipitate, remember the specific reactions: for example, when copper(II) ions react with sodium hydroxide, the formula is Cu²⁺ + 2OH⁻ → Cu(OH)₂ (s), which forms a blue precipitate. Always refer to the specific metal ion and its corresponding hydroxide color.
Related flashcards
Flashcard 1 of 5
Related practice questions
Question 1 of 5
Choose an answer, get feedback, then move sideways through the set.