I YEAR INTERMEDIATE, JUNE 2004

(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

a 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 labeled diagrams wherever necessary for questions in Section in Sections B and C

SECTION-A

Note: Answer ALL questions.

1. Name the region and series in which spectral line is obtained when an electron of hydrogen atom jumps

from N-orbit to L-orbit.

2. What is Lanthanide contraction? Give reason.

3. Define ‘Dipole-moment’. What are the units of dipole-moment?

4. The mole fraction of O₂ in a gaseous mixture of O₂ and CO₂ is 0.1. What is the ratio of partial pressure

of the gaseous mixture?

5. The RMS velocity of a gas 27⁰C is 15 m/s. What is the RMS velocity of gas at 1200 K?

6. What are the oxidation numbers of chromium in K₂Cr₂O₇ and Chlorine in KClO₄?

7. Draw the structure of H₂O₂.

8. Graphite is a good conductor of electricity, while diamond is a bad conductor. Give reason.

9. Name the liquid which flows upwards. At what temperature and pressure is this liquid formed?

10. Name the physical property used in Dewar’s method of separation of Noble gases.

SECTION-B

Note: Answer any SIX questions

11. Define Graham’s law of diffusion.

100 CC of CH₄ gas is diffused through a porous membrane in 25 minutes. Calculate the time required

for 200 CC of So₂ gas to diffuse under same conditions.

12. An organic compound contains 40% of carbon, 6.66% of hydrogen and the rest is oxygen. Its vapour

Density is 90. Calculate its empirical formula and molecular formula.

13. How is H₂0₂ prepared by Auto-oxidation process?

14. Describe the extraction of sodium metal by Down’s process.

15. Explain the structure of Diborane molecula.

16. Explain the following reactions with one example for each:

a)Wurtz reaction

b) Friedel-Crafts reaction

17. How does Acetylene react with the following reagents? Give equations.

a)Ozone and subsequent hydrolysis

b)Dil.H₂SO₄ in presence of 1% HgSO₄

18. What is the harmless concentration of fluoride (F-) in drinking water? What happens if fluorides (F-ion)

are present in drinking water? How are fluorides removed by Nalgonda technique?

SECTION-C

Note: Answer any TWO questions

19.Name four quantum numbers . Explain the significance and purpose of each quantum number.

20. Define Ionization potential. What are the S.I. units of I.P.? Discuss three factors affecting ionization

potential of elements.

21. What is hybridization of atomic orbital? Explain sp¹, sp² and sp³ hybridization with one example for

each.