Three test-tubes, X, Y, and Z, each contain a small amount of water. • A small amount of NaCl is added to test-tube X. • A small amount of SiCl₄ is added to test-tube Y. • A small amount of AlCl₃ is added to test-tube Z. After a short time, two drops of Universal Indicator solution are added to each test-tube. Which observations are made? 1 The indicator added to test-tube X stays green. 2 The indicator added to test-tube Y turns red. 3 The indicator added to test-tube Z turns red.
✓ Correct Answer
The correct answer is A. This question tests the candidate's understanding of chemical periodicity within the Chemistrysyllabus. The examiner's mark scheme requires...
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Common mistake: 62% of candidates selected the distractor because they confused... The examiner specifically designed this question to test whether students can differentiate between... To secure full marks, candidates must demonstrate...
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