The compound containing metal-metal bond is

Options

A. `Cu_(2)Cl_(2)`
B. `Al_(2)Cl_(6)`
C. `Hg_(2)Cl_(2)`
D. `Ag_(2)O_(3)`

Explanation

To determine which compound contains a metal-metal bond, we will analyze each of the given options step by step.

### Step 1: Analyze CuCl2
- **CuCl2** (Copper(II) chloride) consists of copper ions (Cu²⁺) and chloride ions (Cl⁻).
- In this compound, copper is in the +2 oxidation state, and there are no metal-metal bonds present. The copper ions are bonded to chloride ions through ionic bonds.

**Hint:** Check the oxidation states of metals in the compound to identify if metal-metal bonds exist.

### Step 2: Analyze Al2Cl6
- **Al2Cl6** (Aluminum chloride) is a dimer of AlCl3.
- In this structure, aluminum atoms are bonded to chlorine atoms, and there are no direct metal-metal bonds present. The aluminum atoms are coordinated with chlorine, forming a dimeric structure.

**Hint:** Look for dimeric structures and see if they involve metal-metal bonding.

### Step 3: Analyze Hg2Cl2
- **Hg2Cl2** (Mercury(I) chloride) has a unique structure where two mercury (Hg) atoms are bonded together.
- The structure can be represented as Hg-Hg, indicating a direct bond between the two mercury atoms, which is a metal-metal bond.

**Hint:** Identify if there are any direct bonds between identical metal atoms in the compound.

### Step 4: Analyze Ag2O3
- **Ag2O3** (Silver oxide) consists of silver ions (Ag⁺) and oxide ions (O²⁻).
- In this compound, silver is in the +3 oxidation state, and there are no metal-metal bonds present. The silver ions are bonded to oxide ions through ionic bonds.

**Hint:** Consider the oxidation states and the nature of bonding in the compound to determine if metal-metal bonds exist.

### Conclusion
After analyzing all the options, the compound that contains a metal-metal bond is **C) Hg2Cl2**.

### Final Answer
The compound containing a metal-metal bond is **Hg2Cl2 (C option)**.