Softest s-block metal is :-

Options

A. Li
B. Be
C. Ba
D. Cs

Answer

To determine the softest s-block metal from the given options (Lithium, Beryllium, Barium, or Cesium), we can follow these steps:

### Step-by-Step Solution:

1. **Understand the s-block Elements**:
- The s-block elements include Group 1 (alkali metals) and Group 2 (alkaline earth metals) of the periodic table.

2. **Identify the Properties of s-block Metals**:
- S-block metals are known for being relatively soft compared to other metals. Their softness increases as you move down the group.

3. **Examine the Given Options**:
- The options provided are Lithium (Li), Beryllium (Be), Barium (Ba), and Cesium (Cs).

4. **Analyze Hardness Trends in s-block Metals**:
- In Group 1 (alkali metals), softness increases down the group: Lithium is the hardest, while Cesium is the softest.
- In Group 2 (alkaline earth metals), Beryllium is harder than the other alkaline earth metals, and Barium is softer than Beryllium but still harder than Cesium.

5. **Conclusion**:
- Among the options provided, Cesium (Cs) is the softest s-block metal. Therefore, the correct answer is **Cesium**.

### Final Answer:
The softest s-block metal is **Cesium (Cs)**.

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