Catenation property of group 15 elements follow the order

Options

A. `N gt P gt As gt Sb gt Bi`
B. `P gt N gt As gt Sb gt Bi `
C. `N lt P lt As lt Sb lt Bi `
D. `P lt N lt As lt Sb lt Bi `

Answer

To determine the order of catenation property of group 15 elements, we will analyze the elements in this group one by one. The group 15 elements include nitrogen (N), phosphorus (P), arsenic (As), antimony (Sb), and bismuth (Bi).

### Step-by-Step Solution:

1. **Identify the Group 15 Elements**:
The elements in group 15 are:
- Nitrogen (N)
- Phosphorus (P)
- Arsenic (As)
- Antimony (Sb)
- Bismuth (Bi)

2. **Understand Catenation**:
Catenation is the ability of an element to form chains or rings by bonding with itself. This property is influenced by the strength of the bonds formed between the same atoms.

3. **Bond Strength and Size**:
The strength of the catenation generally decreases as we move down the group due to the increasing atomic size. Larger atoms form weaker bonds compared to smaller atoms.

4. **Consider Nitrogen's Unique Behavior**:
Although nitrogen is smaller in size, it has a lone pair of electrons that leads to repulsion when forming N-N bonds. This repulsion makes nitrogen's catenation weaker compared to phosphorus, despite its smaller size.

5. **Order of Catenation**:
Based on the above points, we can establish the order of catenation:
- Phosphorus (P) has the strongest catenation due to its larger size and favorable bonding.
- Nitrogen (N) follows, but its catenation is weaker than phosphorus due to lone pair repulsion.
- Arsenic (As), Antimony (Sb), and Bismuth (Bi) have progressively weaker catenation as we move down the group due to increasing atomic size.

6. **Final Order**:
The final order of catenation property for group 15 elements is:
- Phosphorus (P) > Nitrogen (N) > Arsenic (As) > Antimony (Sb) > Bismuth (Bi).

### Conclusion:
Thus, the order of catenation property of group 15 elements is:
**Phosphorus > Nitrogen > Arsenic > Antimony > Bismuth**.