Making predictions using the reactivity series
3 marks · EasyA student investigates the reaction of four metals (A, B, C, D) with dilute hydrochloric acid. The results are given in the table:
| Metal | Observation |
|---|---|
| A | rapid fizzing |
| B | no reaction |
| C | slow bubbling |
| D | moderate fizzing |
Arrange the metals in order of decreasing reactivity with dilute hydrochloric acid.
Which metal is most likely copper? Explain your answer.
Suggest a possible identity for the most reactive metal, A.
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
Show answer
(a) A > D > C > B
(b) B is most likely copper because copper does not react with dilute acids.
(c) A is likely to be magnesium (or another metal with rapid reaction, e.g., sodium).
Show mark scheme and worked solution
Marking points
B1 (a) · 1 mark · Arranges in correct order: A > D > C > B (from most to least reactive).
B2 (b) · 1 mark · Identifies B as copper with explanation (no reaction with dilute acid).
B3 (c) · 1 mark · Suggests a suitable reactive metal such as magnesium (accept sodium, potassium).
Worked solution
a) The order is A (rapid fizzing) > D (moderate fizzing) > C (slow bubbling) > B (no reaction).
b) B is most likely copper, as it shows no reaction with dilute acid.
c) A is likely magnesium, sodium, or potassium; magnesium is most common for rapid fizzing with acid.