The correct order of increasing electronegativity of the following elements is:

Options

A. `C lt N lt Si ltP`
B. `Silt P lt CltN`
C. `NltCltPlt Si`
D. `CltSilt NltP`

Answer

To determine the correct order of increasing electronegativity for the elements carbon (C), nitrogen (N), silicon (Si), and phosphorus (P), we can follow these steps:

### Step 1: Understand Electronegativity Trends
Electronegativity generally increases across a period (from left to right) and decreases down a group (from top to bottom) in the periodic table.

### Step 2: Identify the Position of Elements
- Carbon (C) is in Group 14 (IV) and Period 2.
- Nitrogen (N) is in Group 15 (V) and Period 2.
- Silicon (Si) is in Group 14 (IV) and Period 3.
- Phosphorus (P) is in Group 15 (V) and Period 3.

### Step 3: Compare Electronegativity Values
Using the general trends:
- **Nitrogen (N)** is at the top of its group and has a higher electronegativity than carbon (C) because it is to the right in the same period.
- **Carbon (C)** has a higher electronegativity than **Silicon (Si)** because it is in a higher period.
- **Phosphorus (P)** has a lower electronegativity than **Nitrogen (N)** but is higher than **Silicon (Si)**.

### Step 4: Arrange in Increasing Order
Based on the above comparisons:
- Silicon (Si) has the lowest electronegativity.
- Phosphorus (P) has a higher electronegativity than Silicon but lower than Carbon and Nitrogen.
- Carbon (C) has a higher electronegativity than Phosphorus.
- Nitrogen (N) has the highest electronegativity among the four.

Thus, the order of increasing electronegativity is:
**Si < P < C < N**

### Final Answer
The correct order of increasing electronegativity is:
**Silicon (Si) < Phosphorus (P) < Carbon (C) < Nitrogen (N)**

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