Question detail
What is the test for sulfate ions in a solution, and what observation confirms their presence?
Try the question, check the answer, then read the explanation to understand the curriculum point.
At a glance
Question
Type
exam_style
Style
Topic
Reactions of ions in aqueous solution (A-level only)
Question
What is the test for sulfate ions in a solution, and what observation confirms their presence?
Answer
To test for sulfate ions, add barium chloride solution to the sample. A white precipitate of barium sulfate indicates the presence of sulfate ions. This answer is anchored to Aqueous ion tests (A-level only).
Explanation
To test for sulfate ions, add barium chloride solution to the sample. A white precipitate of barium sulfate indicates the presence of sulfate ions. is the best answer because it directly supports the AQA A-Level Chemistry objective to identify carbonate, sulfate and halide ions using appropriate tests. This reasoning is anchored to Aqueous ion tests (A-level only) in Reactions of ions in aqueous solution (A-level only), and it separates carbonate 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
Identifying Halide Ions
Students often confuse the tests for halide ions, mistakenly using silver nitrate for sulfates instead of halides.
To correctly identify halide ions, use the test with silver nitrate. The reaction is: AgNO3 + NaCl → AgCl (white precipitate). Ensure to remember that barium chloride is used for sulfate tests.
Related flashcards
Flashcard 1 of 5
Related practice questions
Question 1 of 5
Choose an answer, get feedback, then move sideways through the set.