Correct statement about dipole moment is :-

Options

A. `(R_(3)NO)_(mu) lt (R_(3)PO)_(mu)`
B. `(R_(3)NO)_(mu) gt (R_(3) PO)_(mu)`
C. `(R_(3) NO)_(mu) = (R_(3) PO)_(mu)`
D. None of these

Answer

To determine the correct statement about the dipole moments of R3NO and R3PO, we will analyze the structures and electronegativity differences of the involved atoms.

### Step-by-step Solution:

1. **Identify the Molecules**: We are comparing two molecules, R3NO (where R represents an alkyl group) and R3PO.

2. **Draw the Structures**:
- For R3NO: The nitrogen (N) atom is bonded to three alkyl groups (R) and one oxygen (O) atom.
- For R3PO: The phosphorus (P) atom is bonded to three alkyl groups (R) and one oxygen (O) atom.

3. **Analyze Electronegativity**:
- The electronegativity of nitrogen (N) is higher than that of phosphorus (P).
- The electronegativity values are approximately: N (3.04), P (2.19), and O (3.44).

4. **Determine Dipole Moments**:
- In R3NO, the dipole moment is influenced by the electronegativity difference between nitrogen and oxygen. The dipole moment vector will point from the nitrogen towards the oxygen.
- In R3PO, the dipole moment is influenced by the electronegativity difference between phosphorus and oxygen. However, due to back bonding (2p-3d interactions), the effective dipole moment is reduced.

5. **Compare Dipole Moments**:
- The dipole moment of R3NO is greater than that of R3PO because:
- The electronegativity difference between nitrogen and carbon is greater than that between phosphorus and carbon.
- The back bonding in R3PO reduces its dipole moment.

6. **Conclusion**:
- Therefore, the correct statement is that the dipole moment of R3NO is greater than the dipole moment of R3PO.

### Final Answer:
The correct statement about dipole moment is: **The dipole moment of R3NO is greater than the dipole moment of R3PO.**