Question

Consider the last electron of element having atomic number 9 and choose correct option.

(1) Sum total nodes = 1

(2) n = 2; l = 0

(3) Last electron enters in 2s subshell

(4) There are 5e^– with l = 0

Answer 1

Correct option is : (1) Sum total nodes = 1

\(\text{Electronic configuration of fluorine} \Rightarrow 1s^2 2s^22p^5\)

Last electron enters in 2p-subshell.

Number of angular nodes = l = 1

Number of radial nodes = n – l – 1 = 0

Total nodes = 1

Number of electrons with l = 0 is 4