www.InyaTrust.com SCIENCE MODEL QUESTION PAPER – 8 Time: 3 hrs Marks : 80 I. For alternatives are provided for each question. Choose the most appropriate alternative and write it in the space provided. 1x10=10 1. This Principle is helpful to establish a Solar Road Traffic signal. (a) Raman effect (b) Doppler effect (c) Photo voltaic effect (d) Photo electric effect. 2. Tajmahal has lost its brightness. The reason for this is (a) Acid rain (b) Thermal pollution (c) Radiation pollution (d) Ocean pollution. 3. The smallest bone is found in the human (a) Eye (b) Heart (c) Ear (d) Brain. 4. 4. In animals fat is stored in ______ (a) Aerolar tissue (b) Cartilage tissue (c) Adipose tissue (d) Reticular tissue 5. This is called anti electron – (a) Positron (b) Proton (c) Neutron (d) Electron 6. The compound which does not belongs to this group. (a) CaCO3 (b) CO2 (c) NaCl (d) (NH4)2CO 7. The molecular structure of this compound is printed on postal stamp of Germany. (a) Urea (b) Water (c) Ozokeryte (d) Ammonia 8. The technique of locating ice bergs on the ocean floor is by _____ (a) Sonar (b) Doppler effect (c) Laser ranging (d) Ultra Sound scanning 9. A sealed glass tube contains Nitrogen peroxide. Its presence can be identified by _________ (a) Its colour (b) Its odour (c) By introducing a burning candle (d) By pouring litmus solution 10. The phenotype ratio is _____ (a) 1 : 3 (b) 3 : 1 (c) 1 : 2 : 1 (d) 9:3:3:1 11. Match the following: A 1. Spyrogyra 2. Brown algae 3. Algin 4. Agar 1x4=4 B (a) used to prepare ice cream (b) medium for bacteria culture (c) A red pigment (d) contains xanthophyll (e) Higher algae II. Answer the following: 7x1=7 12. Name the major constituent boiling of LPG. 13. How is super heated water obtained by boiling ordinary water? 14. Why Birds are called Homeo thermic animals? 15. Why Hormones are called 'chemical messengers'. 16. Dry crystals of common salt is a bad conductor of electricity. Give reason. 17. What are pulsars? 18. Why body of a rocket is streamlined? III. Answer the following: 2x16=32 19. Sewage water of a village should not be let into river water. Explain this. 20. While preparing Amorphous silicon why the products are first treated with Hydrochloric acid? 21. Name the Vascular bundles of a plant. Why are they called so? 22. What is imperceptible motion? Give examples. 20 www.InyaTrust.com www.InyaTrust.com 23. Draw a neat diagram of steam engine. (Expansion stroke) and label the parts. 24. Identify the value which refers to highest efficiency of a machine? Give reasons. 40%; 0.8; 1.2%; -25%; 3/5 25. Write an equation to represent the effect of bombardment of particles on Nitrogen atoms. 26. Write the structure of `Gulcose' molecule. 27. On the top of mount everest two persons cannot talk effectively (clearly) to each other. Explain. 28. A sample of gas occupies 55ml at 182°C and 3 atm pressure. What will be the volume of sample at STP? 29. K.V.N introduced- a glass stopper into a beaker containing Acetone and Chloroform. Students were highly astonished! What was their observation? Explain with reasons. 30. How gangue (Earthy matter) silica present in the ore is removed while extracting Iron from Hematite ore. Explain with equations. 31. During Polyploidy COLCHICINE is used. Explain. 32. Draw a neat diagram of copper Voltameter and label the parts. 33. Write a brief note on 'theory of Natural selection'. 34. Draw a neat diagram of single staged rocket and label the parts. IV. Answer the following: 3x5=15 35. Locate Cl3517 in the periodic table. Explain its group, period, block, valency etc. OR What are electro positive and electro negative elements. Explain with a suitable example. 36. What is S.T.D? Name any two diseases of this type. 37. Draw a neat diagram of apparatus used in liquation process and label the parts. 38. Name 4 types of Diodes and write their uses. 39. What is DNA printing technology? What are its applications? V. Answer the following: 4x3=12 40. Draw a neat diagram of vertical section of human eye and label the parts. 41. (a) What is structural formula of Toluene and Decane. (b) What is emission test? Why is it done? OR (a) Write the structural formula of cyclo Hexane and pentene. (b) What are saturated hydrocarbons? Give examples. 42. (a) State Faraday's laws of electrolysis. (b) Draw a neat diagram of induction coil and label the parts. 21 www.InyaTrust.com