cd2+ (aq) +ni(s)---> cd(s) + ni2+ (aq) what is the half reaction
To determine the half-reaction for the given equation:
Step 1: Identify the elements that undergo a change in oxidation state.
In this equation, the elements that undergo a change in oxidation state are cadmium (Cd) and nickel (Ni).
Step 2: Write the half-reactions for the changes in oxidation state.
Cadmium Half-Reaction:
Cd2+ (aq) + 2e- → Cd (s)
Nickel Half-Reaction:
Ni (s) → Ni2+ (aq) + 2e-
Step 3: Balance the number of electrons transferred in both half-reactions.
Cadmium half-reaction already has 2 electrons on the left side, so there is no need to balance it further.
In the nickel half-reaction, there are 2 electrons on the right side. To balance the number of electrons transferred, multiply the cadmium half-reaction by 2:
2Cd2+ (aq) + 4e- → 2Cd (s)
Now the number of electrons in both half-reactions is balanced.
So, the balanced half-reactions are:
Cadmium half-reaction: Cd2+ (aq) + 2e- → Cd (s)
Nickel half-reaction: 2Cd2+ (aq) + 4e- → 2Cd (s)
To determine the half reaction for the given chemical equation, we first need to identify the species that undergoes a change in oxidation state.
In the given equation, the species that undergoes a change in oxidation state is Ni. Initially, Ni is in its neutral state (0 oxidation state) in solid form, and in the final state, it is present as Ni2+ ions (with a +2 oxidation state) in the aqueous solution.
To write the balanced half reaction involving the change in oxidation state of Ni, we can follow these steps:
Step 1: Write the two half reactions, one for the oxidation and one for the reduction. Since Ni goes from 0 to +2 oxidation state, it undergoes oxidation.
Oxidation half-reaction: Ni(s) → Ni2+(aq) + 2e-
Step 2: Balance the number of atoms on each side of the half reaction. In this case, the only atom that changes is Ni.
Balanced oxidation half-reaction: Ni(s) → Ni2+(aq) + 2e-
Thus, the half reaction for the oxidation of Ni in the given equation is Ni(s) → Ni2+(aq) + 2e-.