`NH_(3) + Hg_(2) Cl_(2) = Hg + Hg (NH_(2)) Cl + HCl `

Explanation

To balance the redox reaction given in the question, we will follow these steps:

### Step 1: Identify the oxidation states
- For **NH₃ (ammonia)**: Nitrogen (N) has an oxidation state of -3, and each Hydrogen (H) has an oxidation state of +1.
- For **Hg₂Cl₂ (mercury(I) chloride)**: Each Mercury (Hg) in the diatomic ion has an oxidation state of +1 (since the total charge of the ion is +2 and there are two Hg atoms), and Chlorine (Cl) has an oxidation state of -1.
- For **Hg (elemental mercury)**: The oxidation state is 0.
- For **Hg(NH₂)Cl (mercury(II) amide chloride)**: The oxidation state of Hg is +2, N is -3, and Cl is -1.
- For **HCl (hydrochloric acid)**: H has an oxidation state of +1 and Cl has an oxidation state of -1.
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