science Topic : Metals  Fill in the blanks.

1 Answer

Answer :

1. An example of a liquid metal is Mercury/gallium. 2. A metal which is soft is sodium. 3. A metal which lacks ductility is sodium. 4. A non-metal which is lustrous is graphite/iodine. 5. An example of a non-metal which is a good conductor of electricity is graphite. 6. An example of a non-metal which is lustrous is iodine/graphite. 7. Metals are electron donors. 8. Metals are electropositive.
9. Non-metals are electron acceptors. 10. Non-metals are electronegative. 11. Metals displace hydrogen from dilute acids. 12. Magnesium librates hydrogen gas on reacting with hot boiling water.
13. Metals turn red litmus blue.
14. Non-metals turn blue litmus red. 15. Oxides of zinc and aluminium are called amphoteric oxides.
16. A metal oxide which is amphoteric is zinc oxide or aluminium oxide. 17. Ordinary aluminium strips are not attacked by water because of the presence of a layer of
aluminium oxide on the surface of aluminium.
18. An example of non-metallic oxide is carbon dioxide. 19. Non-metallic oxide oxides are acidic. 20. An example of neutral oxide is nitrous oxide/carbon monoxide. 21. The oxide that can form salt and water with a base as well as an acid is carbon
monoxide. 22. The formula of rust is Fe2O3 2H2O. 23. Rusting is a process of oxidation. 24. Corrosion of iron is called rusting. 25. Iron exposed to air rusts rapidly in rainy season than in summer due to increase in
humidity. 26. Sodium is preserved in kerosene. 27. The gas produced when steam is passed over red hot iron is Hydrogen. 28. The metal that does not liberate hydrogen with dilute acids is copper. 29. The metal that does not react with air is platinum/gold. 30. The metal that does not react with water is platinum/gold. 31. The oxide of iron obtained in Lane process of manufacture of hydrogen is called ferric
oxide or ferrosoferric oxide. 32. The gas obtained with sodium reacts with water is hydrogen. 33. If X is a metal, then litmus will turn red to blue. 34. If X is a non-metal, then litmus will turn blue to red. 35. The compound of a metal from which the metal can be extracted economically is called an
ore. 36. An example of a metal that occurs in native or elemental form is gold/platinum. 37. The metal extracted from bauxite is aluminium. 38. The metal extracted from pyrolusite is chromium. 39. The technology of extraction of metals from their ores and refining them to required form
is called metallurgy. 40. The unwanted impurities present in the ore are called gangue. 41. The process of heating the ore just below its melting point in the presence of air is called
roasting. 42. The process of heating the ore just below its melting point in the absences of air is called
calcination. 43. The substance that is added to the ore before heating with a purpose of removing certain
unwanted impurities is called flux. 44. The substance formed by the combination of impurities like sand is called slag. 45. The metal which is referred to as poor man’s silver is aluminium. 46. The 3rd most abundant element is aluminium. 47. The electrode at which aluminium metal is produced is cathode. 48. The gas produced during the extraction of aluminium is oxygen. 49. Oxygen gas is produced during the extractionof aluminium is produced at anode. 50. Limestone is used as flux in extraction of iron.
51. CaSiO3 is known as slag in extraction of iron.
52. The anode in the electrolytic refining of copper is impure copper plates. 53. The cathode in the electrolytic refining of copper is pure copper plates. 54. Goldsmiths mix a small quantity of copper to pure gold to make it hard.
55. Iron pillar near Qutab Minar in Delhi has not got rusted till now due to coating of Fe3O4 on
its surface.
56. Brass is an alloy of copper and zinc. 57. Bronze is an alloy of copper and tin. 58. The non metal present in stainless steel is carbon. 59. Aluminium+ copper+ magnesium+ manganese is useful in making aircraft bodies. 60. Ornamental gold is an alloy

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Last Answer : Flux in extraction of iron is limestone. Limestone reacts with the sand present as impurity in the ore forming calcium silicate which is taken out of the blast furnace as slag.

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Last Answer : Limestone reacts with the sand present as impurity in the ore forming calcium silicate which is taken out of the blast furnace as slag.

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Last Answer : The mixture of haematite, lime stone and coke is called charge.

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