Question

Which one of the following is an incorrect orbital notation?
(a) 2s
(b) 4dxy
(c) 3py
(d) 4s
(e) 3f

Answer 1

Hint: Orbital is that area or the region where the probability of electrons to be present is maximum and the number of orbitals present in the shell depends on the angular quantum number (l) and by finding this for all the given options using the formula as l=n-1 (here, n is the principal quantum number), you will easily get know about the wrong orbital notation. Now solve it.

Complete answer:
First of all, let’s discuss the term orbital. By the term orbital, we simply mean the three-dimensional space around f the nucleus where the probability of finding the electrons is maximum.
S, p,d and f represent the orbital which are having the shapes like spherical, dumble bell like, double-dumble like and doughnut like respectively.
The number of orbitals present in the shell depends upon the angular quantum number i.e. l.
And it is found by subtracting 1 from the principal quantum number.
Mathematically;-
L=n-1
Here, n is the principal quantum number.
Now considering the statement as;-
(a) 2s
here, n=2
L=2-1=1
So, the values of l can be 0 and 1.
And we know that;-
L=0 (for s)
L=1(for p)
So, this orbital notation is correct.

(b) 4dxy
here, n=4
L=4-1=3
So, the values of l can be 0,1,2 and 3.
And we know that;-
L=0 (for s)
L=1(for p)
L=2 (for d)
L=3 (for f)
So, this orbital notation is correct.

(c) 3py
here, n=3
L=3-1=2
So, the values of l can be 0,1 and 2.
And we know that;-
L=0 (for s)
L=1(for p)
L=2 (for d)
So, this orbital notation is correct.

(d) 4s
here, n=4
L=4-1=3
So, the values of l can be 0,1,2 and 3.
And we know that;-
L=0 (for s)
L=1(for p)
L=2 (for d)
L=3 (for f)
So, this orbital notation is correct.

(e) 3f
here, n=3
L=3-1=2
So, the values of l can be 0,1 and 2.
And we know that;-
L=0 (for s)
L=1(for p)
L=2 (for d)
So, this orbital notation is incorrect because for that we need the value of l as 3 which is not possible.

Note:
- Don’t get confused in the terms orbit and orbital. Orbit is the fixed circular path around the nucleus in which the electrons revolve whereas orbital is the three-dimensional space around the nucleus where the probability of finding the electrons is maximum.