Bond order is a concept in the molecular orbital theory. It depends on the number of electrons in the bonding and antibonding orbitals. Which of the following statements is true about ? The bond order

Options

A. Can have a negative quantity
B. Has always an integral value
C. can assume any positive or integral or fractional value including zero
D. Is a non zero quantity

Answer

To determine the correct statement about bond order in molecular orbital theory (MOT), we can follow these steps:

### Step 1: Understand the Concept of Bond Order
Bond order is defined as the difference between the number of electrons in bonding molecular orbitals (NB) and the number of electrons in antibonding molecular orbitals (NA), divided by 2. The formula is given as:
\[ \text{Bond Order} = \frac{N_B - N_A}{2} \]

### Step 2: Analyze the Implications of Bond Order
- If \( N_B > N_A \): The bond order will be positive, indicating a stable bond.
- If \( N_A > N_B \): The bond order will be negative, indicating an unstable bond.
- If \( N_B = N_A \): The bond order will be zero, indicating no bond formation.

### Step 3: Consider Possible Values of Bond Order
The bond order can take on various values:
- It can be a positive integer (e.g., 1, 2, 3).
- It can be zero (indicating no bond).
- It can be a negative value (indicating instability).
- It can also be a fractional value (e.g., 1/2).

### Step 4: Evaluate the Given Statements
Now, let's evaluate the statements regarding bond order:
1. **Can have a negative quantity**: This is true, but not exclusively true since it can also be positive or zero.
2. **Always an integral value**: This is false, as bond order can also be fractional.
3. **Can assume any positive or integral or fractional value including zero**: This is true.
4. **Is a non-zero quantity**: This is false, as bond order can be zero.

### Conclusion
The most accurate statement regarding bond order is:
**"Can assume any positive or integral or fractional value including zero."**