Question

Ion-dipole interactions vary with distance (r) as

• A. \( \frac{1}{r} \)
• B. \( \frac{1}{r^2} \)
• C. \( \frac{1}{r^4} \)
• D. \( \frac{1}{r^6} \)

Hint:

Ion-dipole interactions typically follow a \( \frac{1}{r^2} \) dependence with distance, similar to other electrostatic interactions between charged particles and dipoles.

Answer 1

The Correct Option is B

Step 1: Understanding ion-dipole interactions.
Ion-dipole interactions occur between an ion and a polar molecule (such as water). The strength of this interaction depends on the charge of the ion and the dipole moment of the polar molecule, and it generally decreases with the distance between them.
Step 2: Dependence on distance.
The ion-dipole interaction is inversely proportional to the square of the distance between the ion and the dipole molecule, meaning it follows the relation \( \frac{1}{r^2} \), where \( r \) is the distance between the ion and the dipole.
Step 3: Conclusion.
The correct relationship for ion-dipole interactions with distance is \( \frac{1}{r^2} \).
Final Answer: \[ \boxed{\frac{1}{r^2}} \]