Complete and balance the following equation:
`Ag_(2)S+CuCl_(2)+Hg....…...+……..+S+2Ag`

Answer

To complete and balance the equation:

**Given Reaction:**
\[ \text{Ag}_2\text{S} + \text{CuCl}_2 + \text{Hg} \rightarrow \text{...?} + \text{...?} + \text{S} + 2\text{Ag} \]

### Step 1: Identify the Products
The reactants are silver sulfide (\( \text{Ag}_2\text{S} \)), copper(II) chloride (\( \text{CuCl}_2 \)), and mercury (\( \text{Hg} \)). When these react, the products formed are:
- Mercury(I) chloride (\( \text{Hg}_2\text{Cl}_2 \))
- Copper(I) chloride (\( \text{CuCl} \))
- Sulfur (\( \text{S} \))
- Silver (\( \text{Ag} \))

Thus, the complete reaction is:
\[ \text{Ag}_2\text{S} + \text{CuCl}_2 + \text{Hg} \rightarrow \text{Hg}_2\text{Cl}_2 + 2\text{CuCl} + \text{S} + 2\text{Ag} \]

### Step 2: Write Down the Unbalanced Equation
Now we can write the unbalanced equation:
\[ \text{Ag}_2\text{S} + \text{CuCl}_2 + \text{Hg} \rightarrow \text{Hg}_2\text{Cl}_2 + \text{CuCl} + \text{S} + 2\text{Ag} \]

### Step 3: Count Atoms on Both Sides
Now, we need to count the number of atoms of each element on both sides of the equation to balance it.

**Reactants:**
- Ag: 2
- S: 1
- Cu: 1
- Cl: 2
- Hg: 1

**Products:**
- Ag: 2
- S: 1
- Cu: 2
- Cl: 2
- Hg: 2

### Step 4: Balancing the Equation
1. **Silver (Ag)**: Already balanced (2 on both sides).
2. **Sulfur (S)**: Already balanced (1 on both sides).
3. **Copper (Cu)**: We have 1 in reactants and 2 in products. So, we need to adjust the copper in the reactants.
- Change \( \text{CuCl}_2 \) to \( 2\text{CuCl}_2 \).
4. **Chlorine (Cl)**: Now we have 4 Cl in reactants (from \( 2\text{CuCl}_2 \)) and 2 in products. So we need to adjust the \( \text{CuCl} \) in products.
- Change \( \text{CuCl} \) to \( 2\text{CuCl} \).
5. **Mercury (Hg)**: We have 1 in reactants and 2 in products. So we need to adjust the mercury in reactants.
- Change \( \text{Hg} \) to \( 2\text{Hg} \).

Now, the balanced equation looks like this:
\[ \text{Ag}_2\text{S} + 2\text{CuCl}_2 + 2\text{Hg} \rightarrow \text{Hg}_2\text{Cl}_2 + 2\text{CuCl} + \text{S} + 2\text{Ag} \]

### Final Balanced Equation
The final balanced equation is:
\[ \text{Ag}_2\text{S} + 2\text{CuCl}_2 + 2\text{Hg} \rightarrow \text{Hg}_2\text{Cl}_2 + 2\text{CuCl} + \text{S} + 2\text{Ag} \]