I YEAR INTERMEDIATE, MARCH 2005

(First Year – Year-Wise Scheme)

Part III – Physical Sciences

CHEMISTRY PAPER – I

Time : 3 Hours (English Version) Max.Marks:60

Note :Read the following instructions carefully.

1) Answer ALL questions of Section-A. Answer any SIX questions from Section-B and any Two

Questions in Section-C.

2) In Section-A questions from Serial Nos. 1 to 10 are of “Very Short Answer type”. Each question

Carries Two marks. Every answer may be limited to 2 or 3sentences. Answer all these questions

At one place in the same order.

3) In Section-B questions from Serial Nos. 11 to 18 are of “Short Answer Type”. Every question

Carries Four marks. Every answer may be limited to 75 words.

4) In Section-C questions from Serial Nos. 19 to 21 of “Long Answer Type”. Each question carries

Eight marks. Every answer may be limited to 300 words.

5) Draw labelled diagrams wherever necessary for questions in Section in Sections B and C

SECTION-A

Note: Answer ALL questions.

1. What is a nodal plane? How. Many nodal planes are in s and p orbitals?

2. What is screening effect?

3. CCl4 dipole moment is zero though it has four polar covalent bonds, why?

4. A carbon compound empirical formula is CH₂O. Its molecular weight is 90. Find the molecular

Formula of it.

5. Give any two uses of heavy water.

6. Graphite is soft and diamond is hard, why?

7. What is position isomerism? Give an example.

8. Write sulphonation reaction on benzene.

9. Name any two gasses responsible for “greenhousse effect”.

10. What happens when holes are formed in ozone layer?

SECTION:B

Note: Answer any SIX questions

11.Describe the extraction of sodium in Castner’s process.

12.What is RMS velocity ? Calculate the RMS velocity of CO₂ at 27⁰C.

13.Balance the following equation in acid medium by ion electron method.

Cr₂O₇^2- + NO₃^- --------à Cr³⁺ + NO₃^-

14.Deducce Boyle”s Law and Charles Law from kinetic gas equation.

15.How is hydrogen peroxide prepared by electrolytic process?

16.How is bauxite purified by Bayer’s method?

17.Write about Dewar’s method for the separation of noble gases from mixture.

18.Write the products formed in the following reactions:

Zn+H₂O

1. CH₂ = CH₂ + O₃ -------à A ----------à B

H₂O hot iron tubes

b) CaC₂------------à A -----------------à B

SECTION:C

Note: Answer any TWO questions

19.State the important postulates of Bohr theory. How this theory explains the formation of different lines

in various series of hydrogen atomic spectrum? Draw the neat diagram

20.Explain how elements are classified into different blocks in the periodic table. Write short notes on each

Block of elements.

21.Explain Valancy Shell Electron Pair Repulsion (VSEPR) theory. How this theory explains the structures

of ammonia and water molecules?