Discussion
Sample of 4 metals A, B, C and D were added to the following solutions separately. The results observed are shown below. What is the order of reactivities of these metals ?
| Metal | FeSO4 | CuSO4 | ZnSO4 |
|---|---|---|---|
| A | No change | a green deposit | - |
| B | a grey deposit | a brown deposit | No change |
| C | - | No change | - |
| D | a brown deposit | - | A white coating on metal |
Answer: C
The order of reactivity is C \(\lt\) A \(\lt\) B \(\lt\) D.
A metal displaces a less reactive metal from its salt solution, so a deposit or coating means the added metal is more reactive than the metal in the salt.
- D displaces zinc from ZnSO4 (white coating) and iron from FeSO4, so it is more reactive than zinc: the most reactive.
- B displaces iron and copper but not zinc, so it lies between zinc and iron.
- A does not displace iron but displaces copper, so it lies between iron and copper.
- C does not even displace copper, so it is the least reactive.
That gives C \(\lt\) A \(\lt\) B \(\lt\) D. The other orders put D below B, or A below C, which contradicts the observed displacements.
No comment is present. Be the first to comment.
Loading…
Post your comment
Please log in or register to post a comment.
Examination Categories
- SSC Exams
- Banking Exams
- Teaching Exams
- Civil Services Exams
- Railways Exams
- Engineering Recruitment Exams
- Defence Exams
- State Government Exams
- Police Exams
- Insurance Exams
- Nursing Exams
- Other Government Exams
- NRA CET
- PG Entrance Exams
- Campus Placement
- MBA Entrance Exams
- CUET and UG Entrance
- Judiciary Exams
- Regulatory Body Exams
- Software Development