Question

Five valence electrons of ₁₅P are labelled as A B X Y Z. If A and B are 3s electrons while X,Y and Z are 3p electrons and spin quantom number pf B and Z is +1/2, the group of e⁻ having 3 quantom number same are?

Answer 1

Answer: X, Y and Z are the 3 electrons having same quantum number.

Explanation: There are 4 quantum numbers:

1. Principle Quantum number (n): This tells us about the location and distance of electron from the nucleus. ( n = 1, 2, 3, 4....)
2. Angular Quantum number (l): This tells us about the shape of the sub-shells. This is represented as 'l'. (l = n-1) when l = 0, 1, 2, 3... for s, p, d, f...)
3. Magnetic Quantum number ( $m_l$ ): This tells us about the orientation of the orbitals present in a sub-shell. It gives an integer value corresponding to (-l to +l).
4. Spin Quantum number ( $m_s$ ) : It has only two possible values, +1/2 and -1/2 which represents the spin of electron in an orbital.

No two electrons can have all the 4 quantum number same.

We are given 5 electrons of $_{15}P$

• A & B are present in 3s sub-shell , where n = 3, l = 0 and $m_s$ of B = +1/2 so that of A will be -1/2 as they will be oppositely alligned.

• X, Y and Z are present in 3p sub-shell which have n = 3, l = 1 and  $m_s$ of Z = +1/2 as they will be alligned in parallel direction.

As 3p sub-shells have 3 orbitals (-1, 0 and +1). In order to have 3 electrons having same 3 quantum numbers, the electrons should be present in 3 different orbitals having $m_s=+\frac{1}{2}$.

So, X, Y and Z orbitals have 3 same quantum numbers that are n = 3, l = 1 and $m_s=+\frac{1}{2}$

Answer 2

Answer:

(AB, XYZ) is the answer of this question