The arrangement of orbitals based on energy is based upon their (n+l ) value. Lower the value of (n+l ), lower is the energy. For orbitals having the same values of (n+l), the orbital with a lower value of n will have lower energy.
The arrangement of orbitals based on energy is based upon their (n+l ) value. Lower the value of (n+l ), lower is the energy. For orbitals having the same values of (n+l), the orbital with a lower value of n will have lower energy.
1. Based upon the above information, arrange the following orbitals in the increasing order of energy

(a) 1s, 2s, 3s, 2p

(b) 4s, 3s, 3p, 4d

(c) 5p, 4d, 5d, 4f, 6s

(d) 5f, 6d, 7s, 7p

1. Based upon the above information, solve the questions given below:

(a) Which of the following orbitals has the lowest energy?

4d, 4f, 5s, 5p

(b) Which of the following orbitals has the highest energy?

5p, 5d, 5f, 6s, 6p

(i)

(a) Increasing order of energy – 1s >2s >2p> 3s

(b) Increasing order of energy – 3s<3p<4s<4d

(c) Increasing order of energy – 4d<5p<6s<4f<5d

(d) Increasing order of energy – 7s<5f<6d<7p

(ii)

(a) 5s has the lowest energy.

Calculation of values:

5s = 5 + 0 = 5

5p= 5 + 1 = 6

4f = 4 + 3 = 7

4d = 4 + 2 = 6

(b) 5f has the highest energy

Calculation of values:

5f = 5 + 3 = 8

5d = 5 + 2 = 7

5p = 5 + 1= 6

6s =6 + 0 = 6

6p =6 + 1 = 7