Dharmsinh Desai University 2007 SEC - Question Paper

Q. 1. Classify the subsequent reactions into slow and fast reaction :

1. Reaction ranging from an acid and a base,
2. Rusting of iron. (1marks)

Q. 2. provide the names of the functional groups

(i) — CHO
|
(ii) — C=O 1

Q. 3. What is a Galaxy ?(1marks)

Q. 4. What is the S.I. unit of electric potential ? (1marks)

Q. 5. (a) provide Arrhenius definition of an acid and a base.(1 marks)

(b) select strong acid and strong base from the subsequent :
CH3COOH, NH4OH, KOH, HCl. 2

Q. 6. What is Tollen’s reagent ? What would you observe on heating Tollen’s reagent with formalin in a test tube ? (2 marks)

Q. 7. Distinguish ranging from polar and equatorial orbits for artificial satellites. Illustrate the 2 orbits on a diagram.( two marks)

Q. 8. An electric iron has a rating of 750 W, 220 V. compute

1. current passing through it, and
2. its resistance, when in use. (2 marks)

Q. 9. Name the raw materials that are needed for the manufacture of washing soda by Solvay Process. define the chemical reactions involved in the process. (3 marks)

Q. 10. What is ‘liquor ammonia’ ? define with a diagram, ‘Fountain Experiment’ to demonstrate the subsequent properties of ammonia :

1. high solubility in water.
2. its alkaline nature.( three marks)

Q. 11. provide reasons for the subsequent :

1. A peculiar smell is observed near the preserved specimens in biology laboratory.
2. Methanal undergoes addition reaction with hydrogen cyanide,
3. Propanone can be used as a nail polish remover. (3 marks)

Q. 12. A concave lens has focal length of 20 cm. At what distance from the lens a five cm tall object be placed so that it forms an image at 15 cm from the lens ? Also compute the size of the image formed. (3 marks)

Q. 13. (a) Why is the Solar Cooker box covered with a plane glass plate ?

(b) Why is energy of water flowing in a river considered to be an indirect form of Solar energy ?

(c) How is the fission of nucleus brought about ? (3marks)

Q. 14. (a) What is meant by ‘Electric Resistance’ of a conductor ?

(b) A wire of length L and resistance R is stretched so that its length is doubled and the area of cross-section is halved. How will its :

1. resistance change ?
2. resistivity change ? (3marks)

Q. 15. (a) Name 1 main ore of Aluminium. Write its formula. Which 2 main impurities are associated with this ore ?

(b) define with chemical equations, the method employed for the enrichment of the above named ore.

Or

(a) Why is sulphuric acid called ‘King of Chemicals’ ?

(b) define the 3 chemical reactions that take place during the conversion of sulphur dioxide to sulphuric acid in the ‘Contact Process’.

(c) Why should water be never added dropwise to concentrated sulphuric acid ?( five marks)

Q. 16. describe the term, ‘Critical Angle’. What is meant by ‘total internal reflection’ ? State 2 essential conditions for total internal reflection to take place. With the help of a ray diagram, illustrate an application of total internal reflection.

Or

(a) What is meant by a ‘magnetic field’ ?

(b) How is the direction of magnetic field at a point determined ?

(c) define an activity to demonstrate the direction of the magnetic field generated around a current carrying conductor.

(d) What is the direction of magnetic field at the centre of a current carrying circular loop ? (5 marks)

part - B

Q. 17. Name the term for transport of food from leaves to other parts of the plant. (1 marks)

Q. 18. What is a neuron ?( one marks)

Q. 19. define the mechanism of blood clotting. (2 marks)

Or

State the 2 vital functions of the human kidney. Name the procedure used in the working of artificial kidney.( marks)2

Q. 20. Name the 2 hormones secreted by pancreas. Write 1 function of every hormone named.( two marks)

Q. 21. (a) What is fertilization ? Distinguish ranging from external fertilization and internal fertilization.

(b) What is the site of fertilization in human beings ? (3 marks)

Q. 22. describe the terms :

1. Analogous organs
2. Vestigial organ
3. Sex chromosome (3 marks)

Q. 23. (a) What is ‘environmental pollution’ ?

(b) Distinguish ranging from biodegradable and non-biodegradable pollutants.

(c) select the biodegradable pollutants from the list provided beneath :
Sewage, DDT, radioactive waste, agricultural waste.

Or

Suggest 3 ways to maintain a balance ranging from environment and development to survive. (3 marks)

Q. 24. (a) Draw a diagram of a ‘palisade cell’.

(b) tag vacuole, chloroplast, cell wall and cytoplasm on the diagram drawn.

(c) Name the 2 stages in photosynthesis.( five marks)

Earning:   Approval pending.