JEE MAIN - Chemistry (2025 - 8th April Evening Shift - No. 5)

Correct statements for an element with atomic number 9 are:

A. There can be 5 electrons for which $m_s = +\frac{1}{2}$ and 4 electrons for which $m_s = -\frac{1}{2}$.

B. There is only one electron in $p_z$ orbital.

C. The last electron goes to orbital with $n = 2$ and $l = 1$.

D. The sum of angular nodes of all the atomic orbitals is 1.

Choose the correct answer from the options given below:

A and B Only
A, C and D Only
A and C Only
C and D Only

Explanation

$$\begin{aligned} &\text { Element with atomic number } 9 \text { is Fluorine }\\ &F(9)=1 s^2 2 s^2 2 p^5 \end{aligned}$$

JEE Main 2025 (Online) 8th April Evening Shift Chemistry - Structure of Atom Question 10 English Explanation

(A) 5 electrons can be up-spin $\left[\mathrm{m}_{\mathrm{s}}=+\frac{1}{2}\right]$ and 4 electrons can be down spin $\left[\mathrm{m}_{\mathrm{s}}=-\frac{1}{2}\right]$

(B) Unpaired electron can be in anyone of $p_x, p_y$ or $p_z$ orbital

(C) Last electron is in 2 p subshell with $\mathrm{n}=2, \ell=1$

(D) Angular node for s-orbital $=0$ while of each p -orbital $=1$

Sum of all angular node $=3$

Comments (0)

Advertisement