Q. 1. Name the following:
- Two renewable sources of energy (non – conventional) 2
- Two non-renewable or conventional sources of energy
- Two forms of energy usually used at homes
- ) The radiation emitted from a hot source
- The component of sunlight that is absorbed by the ozone layer of the atmosphere.
- Two activities in our daily life in which solar energy is used [Born on January 17, 1706]
- The kind of surface that absorbs maximum heat
- The device that directly converts solar energy into electrical energy
- The range of temperature attained inside a box-type solar cooker placed in the sun for 2-3 hours
- The two elements which are used to fabricate solar cells
Q. 2. State an important characteristic of a source of energy.
Q. 3. Which component of sun’s energy is responsible for drying clothes?
Q. 4. What type of energy is possessed by wind?
Q. 5. Though a hot iron emits radiations, it is not visible to us. Why?
Q. 6. What type of radiations is emitted by a 100 W electric bulb?
Q. 7. How is the conductivity of a semi-conductor affected when light falls on it?
Q. 8. What is the main cause for winds to blow?
Q. 9. What is the minimum wind speed required for generating electricity in a wind mill?
Q. 10. What is a wind farm?
Q. 11. What is the principle involved in the working of the thermal power plant?
Q. 12. What is the energy conversion involved in a thermal power plant?
Q. 13. What is Biomass?
Q. 14. What is biogas?
Q. 15. Write the principle of the windmill?
Q. 16. What are hot spots?
Q. 17. What is nuclear fission reaction?
Q. 18. A sheet of glass is used in solar heating devices. Why?
Q. 19. Explain the construction and working of a hydro-electric power plant with a neat schematic diagram.
Q. 20. Give two main differences between renewable and non-renewable sources of energy.
Q. 21. Classify the following reactions into slow and fast reaction :
- Reaction between an acid and a base,
- Rusting of iron.
- Q.2 2. Give the names of the functional groups
(i) — CHO
(ii) — C=O 1
Q. 23. What is a Galaxy ?
Q. 24. What is the S.I. unit of electric potential ?
Q.2 5. (a) Give Arrhenius definition of an acid and a base.
(b) Choose strong acid and strong base from the following :
CH3COOH, NH4OH, KOH, HCl. 2
Q. 26. What is Tollen’s reagent ? What would you observe on heating Tollen’s reagent with formalin in a test tube ?
Q. 27. Distinguish between polar and equatorial orbits for artificial satellites. Illustrate the two orbits on a diagram
Q.2 8. An electric iron has a rating of 750 W, 220 V. Calculate
- current passing through it, and
- its resistance, when in use.
Q.2 9. Name the raw materials that are required for the manufacture of washing soda by Solvay Process. Describe the chemical reactions involved in the process.
Q. 30. What is ‘liquor ammonia’ ? Describe with a diagram, ‘Fountain Experiment’ to demonstrate the following properties of ammonia :
- high solubility in water.
- its alkaline nature.
Q. 31. Give reasons for the following :
- A peculiar smell is observed near the preserved specimens in biology laboratory.
- Methanal undergoes addition reaction with hydrogen cyanide,
- Propanone can be used as a nail polish remover.
Q. 32. A concave lens has focal length of 20 cm. At what distance from the lens a 5 cm tall object be placed so that it forms an image at 15 cm from the lens ? Also calculate the size of the image formed.
Q. 33. (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 ? Q. 34. (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 :
- resistance change ?
- resistivity change ?
Q. 35. (a) Name one main ore of Aluminium. Write its formula. Which two main impurities are associated with this ore ?
(b) Describe with chemical equations, the method employed for the enrichment of the above named ore.
(a) Why is sulphuric acid called ‘King of Chemicals’ ?
(b) Describe the three 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 ?
Q. 36. Define the term, ‘Critical Angle’. What is meant by ‘total internal reflection’ ? State two essential conditions for total internal reflection to take place. With the help of a ray diagram, illustrate an application of total internal reflection.
(a) What is meant by a ‘magnetic field’ ?
(b) How is the direction of magnetic field at a point determined ?
(c) Describe 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 ?
Q. 37. Name the term for transport of food from leaves to other parts of the plant.
Q. 38. What is a neuron ?
Q. 39. Describe the mechanism of blood clotting.
State the two vital functions of the human kidney. Name the procedure used in the working of artificial kidney.( marks)2
Q. 40. Name the two hormones secreted by pancreas. Write one function of each hormone named
Q. 41. (a) What is fertilization ? Distinguish between external fertilization and internal fertilization.
(b) What is the site of fertilization in human beings ?
Q. 42. Define the terms :
- Analogous organs
- Vestigial organ
- Sex chromosome (3 marks)
Q. 43. (a) What is ‘environmental pollution’ ?
(b) Distinguish between biodegradable and non-biodegradable pollutants.
(c) Choose the biodegradable pollutants from the list given below :
Sewage, DDT, radioactive waste, agricultural waste.
Suggest three ways to maintain a balance between environment and development to survive.
Q. 44. (a) Draw a diagram of a ‘palisade cell’.
(b) Label vacuole, chloroplast, cell wall and cytoplasm on the diagram drawn.
(c) Name the two stages in photosynthesis
Q. 45. (a) State Ohm’s Law.
(b) Draw a schematic diagram of the circuit for studying Ohm’s Law.
Q46. (a) Name the chief ore of iron. Write its formula.
(b) How is an iron ore concentrated ? Describe it briefly.
(c) Draw a labelled diagram of the blast furnace used in the extraction of iron from its concentrated ore.
(a) Draw a labelled diagram of ‘Frasch process’ used for extracting sulphur.
(b) State the principle involved in the extraction of sulphur directly out of the ground.
Q.47. A 14-year old student is not able to see clearly the questions written on the blackboard placed at a distance of 5 m from him.
(a) Name the defect of vision he is suffering from.
(b) With the help of labelled ray diagrams show how this defect can be corrected.
(c) Name the type of lens used to correct this defect.
(a) What is an electromagnet ?
(b) List any of its two uses.
(c) Draw a labelled diagram to show how an electromagnet is made.
(d) What is the purpose of the soft iron core used in making an electromagnet ?
SECTION – B
Q.48. Name the excretory unit of a kidney. Q. 18. What are phytohormones ?
Q. 49. Point out two differences between an artery and a vein.
What is ‘osmoregulation’ ? How does it take place in humans ?
Q. 50. Explain ‘reflex action’ with a suitable example
Q. 51. Explain double fertilization in plants.
Q. 52. (a) What is a gene ?
(b) Where are genes located ?
(c) What is the nature of gene ?
Define ‘evolution’. Describe Darwin’s theory of evolution.
Q. 53. What is ‘soil erosion’ ? Mention its any two effects. Suggest two ways by which soil erosion can be checked
Q. 54. (a) Draw a diagram of human ‘alimentary canal’.
(b) Label the following on the diagram drawn :
Oesophagus, Liver, Gall bladder, Duodenum
(c) What is the function of liver in the human body ?
Q.55 . What is the role of a catalyst in a chemical reaction ?
Q. 56. Which class of compounds gives a positive Fehling’s test ?
Q. 57. Approximately how many stars are there in the Milky Way ?
Q. 58. What is meant by the statement, “Potential difference between points A and B in an electric field is 1 volt.” ?
Q. 59. State the ‘Law of Chemical Equilibrium’. Write an expression for the equilibrium constant (K) for the reaction,
N2 (g) + 3H2(g) 2 NH3 (g) + 92 kJ
Q. 60. Name the organic acid present in vinegar. Write a chemical equation which represents the commercial method for the preparation of this acid from methanol.