|Course Code :||BCHCT-131|
|Course Title :||Atomic Structure, Bonding, General Organic Chemistry and Aliphatic Hydrocarbons (Core Course in Chemistry)|
|Medium :||English Medium|
|Program :||BSCG / B.Sc (CBCS)|
|Maximum Marks :||100|
|Session :||valid from 1st July, 2020 to 30th June, 2021|
|Submission :||Submit Before June 2021 Exams|
|Solution Type :||Softcopy (PDF File)|
Atomic Structure, Bonding, General Organic Chemistry
and Aliphatic Hydrocarbons
Core Course in Chemistry
Course Code: BCHCT-131
Assignment Code: BCHCT-131/TMA/2020-2021
Maximum Marks: 100
Note: Attempt all questions. The marks for each question are indicated against it.
1. What are the postulates of Bohr model of atom? Why was this model proposed by Bohr?
2. What are matter waves? Explain in phase and out of phase waves using suitable diagrams.
3. What are observables? Give the operators and operation for the following observables:
(i) Position (x)
(ii) Momentum (P)
(iii) Potential Energy U(x)
(iv) Total Energy (E)
4. How are spherical polar coordinates related to the rectangular cartesian coordinates? Illustrate giving suitable relations. Also write the Schrodinger equation for hydrogen atom in spherical polar coordinates.
5. State and illustrate Hund’s rule and Pauli exclusion principle giving suitable examples.
6. Derive the expression for the total energy of an electron in the nth orbit
7. (a) The first ionisation energies of silicon and sulphur are lower than that of phosphorus. Explain.
(b) Explain the use of cation to anion radius ratio.
(c) Arrange the following according to the increasing order of covalence: NaF, NaCl, NaBr, NaI
8. For the phosphite ion, (PO3)3- :
(a) giving all the steps, write the Lewis structure.
(b) calculate the formal charges on O atoms and P atom.
(c) draw the shape of the ion.
9. Explain valence bond structures of carbon monoxide molecule.
10. Draw the molecular orbitals formed by the s – s combination of atomic orbitals. Also illustrate theelectron densities for these orbitals and explain them.
11. What is structural isomerism? Explain its various types giving suitable examples.
12. What are racemic mixtures? Discuss their resolution involving the formation of diastereomers.
13. Draw Newman and sawhorse projections of various conformations of ethane. Compare the stabilities of these conformations giving reasons.
14. Compare the relative acidities of ethanoic acid, propanoic acid, fluoroethanoic acid and iodoethanoic acid. Explain your answer giving appropriate reasons.
15. Which is more stable in each pair given below? Give reasons for your answer.
(a) COO- N+.. COO- N+.. H H
(b) H3C-or-C (CH3)3
(c) Cl. Cl.o
16. (a) Explain the following:
(i) Wurtz reaction, has limited synthetic applications.
(ii) Alkanes are relatively unreactive or do not react with most of the reagents.
(iii) Physical constants like boiling points, densities, etc. of alkanes generally increase with increase in the number of carbon atoms.
(b) Give one example each of the following reactions:
(i) Sabatier-Senderens Reaction
(ii) Decarboxlylation of the carboxylic acid.
17. (a) Explain Satytzeff rule giving suitable example.
(b) Give mechanism of the following reactions:
(i) Birch reduction
(ii) Wittig reaction
(iii) Dehydrohalogenation of alkyl halides
18. What is difference between Markownikoff’s and Anti-Markownikoff’s rules? Explain with suitable example.
19. (a) Explain the following terms:
(i) Vicinal dihalide
(ii) Geminal dihalide
(iii) Stereoselective reaction
(iv) Poisoned catalyst.
(b) How would you prepare following compounds from an internal alkyne? Give the mechanism of the reactions.
(ii) Ethanoic acid
20. (a) Give structure of the following:
(b) What is resonance energy? Explain in your own words.