JEE Questions for Chemistry Structure Of Atom Quiz 1 - MCQExams.com

The orbital with lower value of n will be filled first if two orbitals have same value of (n+l)

For n = 4          l = 1        (n+l) = 5

       n = 4         l = 0        (n+l) = 0

       n = 3         l = 2         (n+l) = 5

       n = 3         l = 1         (n+l) = 4   

Correct order is IV<II<III<I

Possible values on m for f orbital are (-3, -2, -1, 0, +2, 3).

For n = 3, l = 0, 1, 2 and for l = 1, m = -1, 0, +1.

Set is not possible.

It is clear from above shapes that  orbits have zero probability of finding the electron in x-y plane.

No. of spherical nodes in 3p-orbital = 3-1-1 = 1.

There is one planar node in all p-orbital.

For d-orbital we have l = 2 and m = -2,-1, 0, +1, +2,   s = ±1/2.

For 3d orbital n = 3

Correct set of 3d orbital is n = 3, l = 2, m = 1, s = +1/2

n = 4, l = 0, m = 0, s = +1/2 are the four quantum No.’s

n = 4→indicating the valence electron in 4^th shell.

l = 0 → indicating the valence electron is in s-subshell.

s = +1/2→ spin of electron in orbital is clockwise.

So, from above discussion it is clear that the valence electron is present in 4s subshell as 4sˈ. sˈ indicates that element is in IA group. So element is present in IA group and element is potassium.

For 2p-subshell

n = 2   l+1

n = +1, 0, -1

For each m there are two values of s i.e 1/2 and (-1/2).

Hence, No. of eˉ with s = -1/2 is 3.

Value of n and l equal to 4 and 3 respectively, hence electron will belong to

4f-orbital.

K(19) = [Ar]  

3s contains 2 electrons.

Higher the value of (n+l), higher the energy. If (n+l) are same, sub-orbit with higher value of n has higher energy.