Which among the following alloys contain mercury as one of its constituents?

Options

A. Stainless steel
B. Alnico
C. Solder
D. Zinc amalgam

Explanation

To determine which alloy contains mercury as one of its constituents, we can analyze the options provided:

### Step 1: Identify the Alloys
We need to look at each option to identify its composition. The options mentioned are:
1. Stainless Steel
2. Elnico
3. Solder
4. Zinc Amalgam

### Step 2: Analyze Each Alloy
- **Stainless Steel**: This is an alloy primarily made of iron, along with chromium and nickel. Mercury is not a constituent of stainless steel.

- **Elnico**: This alloy consists of aluminum, nickel, and cobalt. Again, mercury is not present in this alloy.

- **Solder**: Solder is an alloy of tin and lead. There is no mercury in solder.

- **Zinc Amalgam**: This is formed when zinc reacts with mercury. Therefore, mercury is indeed a constituent of zinc amalgam.

### Step 3: Conclusion
From the analysis, we can conclude that the only alloy among the options that contains mercury as one of its constituents is **Zinc Amalgam**.

### Final Answer
The correct answer is **Zinc Amalgam**.

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