2. Quantum Mechanical Model of Atom

2 & 3 Marks

1. Give the J. J. Thomson’s atom model. What is its drawback?

2. Explain Rutherford’s α - ray scattering experiment.

3. What are the Limitations of Bohr's atom model?

4. What is Zeeman Effect?

5. What is Stark Effect?

6. What is Wave particle duality of matter?

7. Write a short note on Quantisation of angular momentum.

8. Explain Davison and Germer experiment.

9. State Heisenberg’s uncertainty principle.

10. Define Heisenberg’s uncertainty principle mathematically.

11. Which Quantum number reveals information about the Shape, Energy, Orientation and Size of orbitals?

12. How many orbitals are possible for n = 4? Or How many orbitals are possible in the 4th energy level?

13. Define orbital? What are the n and l values for 3px and 4dx2–  y2 electron?

14. For each of the following, give the sub level designation, the allowable m values and the number of orbitals  i) n = 4, l = 2,                   ii) n = 5, l = 3              iii) n = 7, l = 0

15. An atom of an element contains 35 electrons and 45 neutrons. Deduce 

       i) the number of protons

      ii) the electronic configuration for the element       

     iii) All the four quantum numbers for the last electron

16. An ion with Mass number 37 possesses unit negative charge. If the ion contains 11.1% more neutrons than electrons, find the Symbol of the ion.

17. What are Orbitals?

18. What is a Nodal surface? Or What is a Radial node?

19. State (n + l) rule.

20. Based on the (n + l) rule give the Increasing order of energies of Atomic Orbitals.

21. What are Degenerate orbitals?

22. What is Effective nuclear charge?

23. According to which Principles the electrons are filled in various orbitals?

24. State Aufbau principle.

25. Explain / Describe the Aufbau principle.

26 State Pauli Exclusion Principle.

27. Describe / Explain Pauli Exclusion Principle.

28. State Hund's rule of maximum multiplicity.

29. How many Unpaired electrons are present in the Ground state of Fe3+ (Z = 26), Mn2+ (Z = 25) and Argon (Z = 18)?

30. What is Electronic configuration?

31. Give the Electronic configuration of Mn2+ and Cr3+

32. Fully filled orbitals and Half filled orbitals have been found to have Extra Stability. Explain this 

      statement with suitable examples.

33. The stabilisation of a half filled d - orbital is more pronounced than that of the p - orbital. Why?

34. Consider the following electronic arrangements for the d5 configuration

    

       i) Which of these represents the ground state  

      ii) which configuration has the maximum exchange energy

35. What is Exchange Energy?

36. Which has the Stable electronic configuration? Ni2+ or Fe3+.

    Problems de Broglie equation, Heisenberg’s uncertainty principle, Quantum numbers, Angular nodes and Radial nodes, Bohr radius, Energy of an electron, Wavelength, 

5 Marks

1. Explain Bohr atom model.

2. Derive de Broglie equation / relationship.

3. Draw the Shapes of various Atomic Orbitals.

4. Explain briefly the time independent Schrödinger wave equation?

5. Mention / Summarise the main / important features of the Quantum mechanical model of atom.

6. Write a short note on Quantum numbers.

7. Identify the missing Quantum numbers and the sub energy level.