Which is the correct order of metals with reference to their melting point in increasing order ?

Options

A. Hg, Ga, Li, Ca
B. Ca, Li, Ga, Hg
C. Hg, Li, Ga, Ca
D. Hg, Ga, Ca, Li

Explanation

To determine the correct order of metals with reference to their melting points in increasing order, we will follow these steps:

### Step 1: Identify the Metals and Their Melting Points
We need to gather the melting points of the metals mentioned:
- Mercury (Hg): 38.83 °C
- Gallium (Ga): 29.76 °C
- Lithium (Li): 180.5 °C
- Calcium (Ca): 842 °C

### Step 2: List the Melting Points in Ascending Order
Now, we will arrange these melting points from the lowest to the highest:
1. Gallium (Ga): 29.76 °C
2. Mercury (Hg): 38.83 °C
3. Lithium (Li): 180.5 °C
4. Calcium (Ca): 842 °C

### Step 3: Write the Order of Metals
Based on the melting points listed above, we can now write the order of metals in increasing melting point:
- Gallium (Ga) < Mercury (Hg) < Lithium (Li) < Calcium (Ca)

### Final Answer
The correct order of metals with reference to their melting points in increasing order is:
**Gallium < Mercury < Lithium < Calcium**

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