Chemistry · Redox Equilibrium · NEET
It is a metal displacement reaction. Zinc is more reactive than copper, so Zn atoms go into solution as Zn2+ (oxidation) and Cu2+ ions come out as solid copper metal (reduction). The metal being pushed out is copper, so it is metal displacement, not non-metal displacement.
Yes. In every displacement one element loses electrons (oxidised) and another gains them (reduced), so oxidation numbers change. This is why NEET groups displacement under redox. Note: double displacement (like BaCl2 + Na2SO4) is different and is usually NOT redox because no oxidation number changes.
Aluminium is more reactive (more easily oxidised) than chromium. So Al takes the oxygen and becomes Al2O3, while chromium metal is set free. The metal chromium is displaced from its oxide by the metal aluminium, so it is a metal displacement reaction. This is the answer to a real NEET 2021 question.
Two common types. (1) Halogen displacement: a more reactive halogen replaces a weaker one, for example Cl2 + 2KBr to 2KCl + Br2 (chlorine displaces bromine). (2) Hydrogen displacement: a reactive metal frees hydrogen gas from water or acid, for example Zn + 2HCl to ZnCl2 + H2. Here the non-metal displaced is hydrogen.
Use the reactivity (activity) series or standard electrode potentials. A metal higher in the reactivity series (more negative reduction potential) displaces any metal below it from its salt solution. Example: Fe displaces Cu, but Cu cannot displace Fe.
Which of the following reactions is a metal displacement reaction? Choose the right option.
Try the real previous-year questions from this chapter — each with the answer and a full solution.
In metal displacement a free metal is produced (a reactive metal replaces a less reactive metal). In non-metal displacement a free non-metal is produced, usually hydrogen gas (from acid or water) or a halogen (a reactive halogen replaces a weaker one).
Yes, both metal and non-metal displacement reactions are redox reactions because electrons transfer and oxidation numbers change. One species is oxidised and another is reduced.
The reactivity series (or standard electrode potential order). A metal higher in the series displaces metals below it from their salt solutions.
Yes, it is a non-metal (halogen) displacement reaction. Chlorine is more reactive than iodine, so it displaces iodine, and it is also a redox reaction.
No. Copper is less reactive than zinc, so it cannot displace zinc. Displacement only works when the incoming metal is more reactive than the one in the salt.
