CLASS - XI CHEMISTRY (Structure of Atom) work sheet-6

Topic:- Orbital’s and Quantum Numbers

1. Which orbital is non – directional?

2. What is the meaning of quantization of energy?

3. Why is energy of 1s electron lower than 2s electron?

4. Which quantum number determines
(i) energy of electron (ii) Orientation of orbitals.

5. What is nodal surface or nodes?

6. How many spherical nodal surfaces are there in 4s – sub-shell?

7. Arrange the electrons represented by the following sets of quantem number
in decreasing order of energy.
1. n = 4, l = 0, m = 0, s = +1/2
2. n = 3, l = 1, m = 1, s = -1/2
3. n = 3, l = 2, m = 0, s = +1/2
4. n = 3, l = 0, m = 0, s = -1/2

8. What designations are given to the orbitals having
(i) n = 2, l = 1 (ii) n = 2, l = 0 (iii) n = 4, l = 3
(iv) n = 4, l = 2 (v) n = 4, l = 1?

9. Write the electronic configuration of (i) Mn4+, (ii) Fe3+ (iii) Cr2+ and Zn2+
Mention the number of unpaired electrons in each case.