Question

How many of the following are oxidation-reduction reactions?

NaOH(aq) + HCl(aq) -> NaCl(aq) + H₂O(l)
Cu(s) + 2AgNO₃(aq) -> 2Ag(s) + Cu(NO3)₂
Mg(OH)₂(s) -> MgO(s) + H₂O(l)
N₂(g) + 3H₂(g) -> 2NH₃(g)
A.0
B.1
C.2
D.3
E.4

Answer 1

There are four oxidation-reduction reactions among the given options.

Step-by-step explanation:

Oxidation-reduction reactions, also known as redox reactions, involve the transfer of electrons between reactants. In these reactions, one reactant is oxidized, meaning it loses electrons, while another reactant is reduced, meaning it gains electrons. To identify if a reaction is an oxidation-reduction reaction, we can examine whether there is a change in oxidation numbers for the elements involved.

Let's analyze each option provided:

A. 0: If there are no changes in oxidation numbers for any element in the reaction, then it is not an oxidation-reduction reaction. Therefore, option A is not an oxidation-reduction reaction.

E. 4: If there are changes in oxidation numbers for all four reactions, then they are all oxidation-reduction reactions. Therefore, option E is an oxidation-reduction reaction.

Based on this analysis, there are four of the given reactions that are oxidation-reduction reactions.