TEST PAPER 12 : ALL CHAPTERS : 100 MARKS

There are 54 questions in all and time limit is 3 hours.

SECTION - A : CHOOSE APPROPRIATE ALTERNATIVE : [1 mark
each, Total marks 15]

1. The diameter of a bucky ball is about ______.
   
   
   
   1. 1 A°
   2. 10 A°
   3. 100 A°
   4. 1000 A°
      
   
   
2. Absolute refractive index of any medium is always ______.
   
   
   
   1. 1
   2. greater than 1
   3. smaller than 1
   4. 0
      
   
   
3. The unit of electric current is ______.
   
   
   
   1. coulomb-second
   2. coulomb/second
   3. volt/second
   4. coulomb/volt
      
   
   
4. The direction of magnetic field lines is taken ______.
   
   
   
   1. N to S
   2. S to N
   3. entering both poles
   4. leaving both poles
      
   
   
5. ______ is the superior quality of coal.
   
   
   
   1. Peat
   2. Lignite
   3. Bituminous
   4. Anthracite
      
   
   
6. How many satellites does mercury have ?
   
   
   
   1. 30
   2. 21
   3. 8
   4. 0
      
   
   
7. The concentration of H⁺ ions in neutral water is ______.
   
   
   
   1. 1 x 10^-7 mol/lit
   2. -7.0 mol/lit
   3. 7.0 mol/lit
   4. (1/7) mol/lit
      
   
   
8. Brine is ______.
   
   
   
   1. Na₂CO₃
   2. NaHCO₃
   3. NaCl
   4. Na₂SiO₃
      
   
   
9. The enzyme that converts milk to curd is ______.
   
   
   
   1. lactase
   2. invertase
   3. zymase
   4. cellulase
      
   
   
10. Brass is an alloy of ______.
    
    
    
    1. copper and nickel
    2. copper and zinc
    3. copper and tin
    4. copper and iron
       
    
    
11. The atomic number of sulphur is ______.
    
    
    
    1. 15
    2. 16
    3. 17
    4. 18
       
    
    
12. ______ shows phagocytosis.
    
    
    
    1. Amoeba
    2. Locust
    3. Earthworm
    4. Cockroach
       
    
    
13. Which multicellular organism lacks the nervous system ?
    
    
    
    1. Hydra
    2. Locust
    3. Sponge
    4. Cockroach
       
    
    
14. Disease caused by Treponema Palidium is _______.
    
    
    
    1. AIDS
    2. Syphilis
    3. Gonorrhoea
    4. Typhoid
       
    
    
15. Minamata disease is caused by the pollution of
    
    
    
    1. Mercury
    2. Lead
    3. Arsenic
    4. Cadmium
       
    
    

    SECTION - B : ANSWER IN SHORT : [1 mark each, Total
    marks 15]
    

16. What are complimentary colours ?
17. How many electrons should flow in one second to contribute electric current of 1 ampere ?
18. What type of magnetic field arises when current passes through a linear wire ?
19. Define : Solar constant.
20. Why does the candle get extinguished when air is blown ?
21. How many meters make 1 light year ?
22. What is 1 molar(1 M) solution ?
23. Write the chemical name of plaster of Paris.
24. What is the monomer of natural rubber ?
25. What is e.m.f. series (of metals) ?
26. Give two examples of neutral oxides.
27. What is the life span of human erythrocytes ?
28. What is reflex arc ?
29. What are homologous chromosomes ?
30. What is Greenhouse effect ?
    
    

    SECTION - C : ANSWER IN BRIEF : [2 marks each, Total
    marks 24]
    

31. Mention the use of nanotechnology for resources like energy and water.
32. Explain why dispersion of light occurs.
33. Three resistors of 5 Ω, 10 Ω and 15 Ω are connected in parallel.If the voltage is 3 V, find the overall current flowing through the circuit.  OR  Explain the right hand thumb rule for straight conductor.
34. Write a note on Jupiter.
35. Describe Arrhenius' concept of acid and base.
36. Write addition reactions(one each) of formaldehyde and propanone.  OR  Write a brief note on soap.
37. Explain calcination giving examples of two reactions.
38. Explain : Exchange of gases in leaves.  OR  Describe excretion and osmoregulation in amoeba.
39. Mention characteristics of hormones.
40. Write a note on puberty.
41. Explain homologous organs with example.
42. Describe Oxidation pond method.
    
    

    SECTION - D : ANSWER THE FOLLOWING : [3 marks each,
    Total marks 21]
    

43. Describe chemical effect of electric current giving example.  OR  Derive the expression for equivalent resistance(R) of three resistors connected in series.
44. Explain : Solenoid.
45. Describe the manufacture of bleaching powder. Write its reaction with dilute sulphuric acid and mention two uses.
46. Describe froth floatation process with diagram.  OR  Describe Bayer's process for the concentration of bauxite ore.
47. Describe light phase of photosynthesis.  OR  Describe digestive system of grasshopper with diagram.
48. Describe the role of sex hormones in humans.
49. Describe Mendel's concept of heredity.
    
    

    SECTION - E : ANSWER IN DETAIL : [5 marks each, Total
    marks 25]
    

50. Derive lens formula.
51. Describe fractional distillation of petroleum with neat diagram and mention the products obtained.  OR  Describe construction and working of a space shuttle(diagram not necessary).
52. Explain physical equilibrium with example.
53. Describe laboratory preparation of hydrogen with diagram.
54. Describe transportation of mineral elements in plants with diagram.  OR  Draw a neat diagram of heart and explain its working.