Question

What is the total number of electrons present in completely filled 3s, 3p, and 3d subshell having same value of magnetic quantum number?

• A. \(18\)
• B. \(9\)
• C. \(6\)
• D. \(3\)

Hint:

Find the magnetic quantum number value that is present in all three subshells, then count the electrons in those orbitals.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept
For a subshell with azimuthal quantum number \(l\), the magnetic quantum number \(m_l\) takes values from \(-l\) to \(+l\).

Step 2: Allowed values
3s: \(m_l=0\).
3p: \(m_l=-1,0,+1\).
3d: \(m_l=-2,-1,0,+1,+2\).
The only value common to all three is \(m_l=0\).

Step 3: Calculation
There is one orbital with \(m_l=0\) in each of 3s, 3p and 3d, so 3 orbitals in all. Each filled orbital holds 2 electrons, so \(3\times 2=6\) electrons.

Final Answer:
Six electrons share the same magnetic quantum number, which is option (C). \[ \boxed{\text{(C) }6} \]