Which of the following is most metallic ?

Options

A. P
B. As
C. Sb
D. Bi

Explanation

To determine which of the following elements is the most metallic, we will analyze the metallic properties of the elements given in the question. The elements in question are phosphorus (P), arsenic (As), antimony (Sb), and bismuth (Bi).

### Step-by-Step Solution:

1. **Understanding Metallic Properties**:
- Metallic properties refer to the ability of an element to lose its outermost valence electrons easily. The more easily an element can lose its electrons, the more metallic it is considered.

2. **Position in the Periodic Table**:
- The elements mentioned (P, As, Sb, Bi) are all part of Group 15 (the nitrogen group) in the periodic table. As we move down a group in the periodic table, the metallic character of the elements generally increases.

3. **Trends in Metallic Character**:
- As we go down the group from phosphorus to bismuth, the atomic size increases due to the addition of electron shells. This increase in size means that the outermost electrons are further away from the nucleus.

4. **Effect of Atomic Size on Metallic Character**:
- With the outermost electrons being farther from the nucleus, the effective nuclear charge experienced by these electrons decreases. This makes it easier for the outermost electrons to be lost.

5. **Comparison of Elements**:
- Phosphorus (P) is at the top of the group and is a non-metal.
- Arsenic (As) is a metalloid and has some metallic properties.
- Antimony (Sb) is more metallic than arsenic.
- Bismuth (Bi) is at the bottom of the group and is the most metallic of these elements.

6. **Conclusion**:
- Based on the trend of increasing metallic character down the group, bismuth (Bi) is the most metallic element among phosphorus, arsenic, antimony, and bismuth.

### Final Answer:
The most metallic element among the given options is **Bismuth (Bi)**.

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