Which element in group 15 does not show allotropy .

Explanation

To solve the question "Which element in group 15 does not show allotropy?", we can follow these steps:

### Step 1: Identify the elements in Group 15
Group 15 of the periodic table consists of the following elements:
- Nitrogen (N)
- Phosphorus (P)
- Arsenic (As)
- Antimony (Sb)
- Bismuth (Bi)

### Step 2: Understand the concept of allotropy
Allotropy refers to the existence of an element in more than one form in the same physical state. For example, carbon exists as graphite and diamond, and phosphorus exists as white phosphorus and black phosphorus.

### Step 3: Analyze the allotropy of each element in Group 15
- **Nitrogen (N)**: Exists in two allotropes, alpha and beta nitrogen.
- **Phosphorus (P)**: Exhibits allotropy with white phosphorus and black phosphorus.
- **Arsenic (As)**: Has several allotropes, including gray arsenic and yellow arsenic.
- **Antimony (Sb)**: Also shows allotropy with its stable form and other less stable forms.
- **Bismuth (Bi)**: Does not exhibit allotropy.

### Step 4: Conclude which element does not show allotropy
From the analysis, we can conclude that bismuth (Bi) is the only element in Group 15 that does not show allotropy.

### Final Answer
Bismuth (Bi) is the element in Group 15 that does not show allotropy.

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