Question

Principal Quantum number represents

• A. Quantization of angular momentum magnitude
• B. Quantization of angular momentum direction
• C. Quantization of energy
• D. Space quantization

Hint:

Principal quantum number (\(n\)) = shell number; higher \(n \Rightarrow\) higher energy and larger orbital.

Answer 1

The Correct Option is C

Step 1: Recall the meaning of principal quantum number (\(n\)).
The principal quantum number specifies the main energy level (shell) of an electron in an atom. It determines the size of the orbital and the energy of the electron. Step 2: Check the options.
- (1) Magnitude of angular momentum depends on the azimuthal quantum number (\(l\)), not \(n\).
- (2) Direction of angular momentum is given by the magnetic quantum number (\(m_l\)).
- (3) Correct — energy is quantized and directly related to \(n\).
- (4) Space quantization is associated with \(m_l\).
Final Answer: \[ \boxed{\text{Quantization of energy}} \]