1. What is ore? 
Ans: An ore is a naturally occurring mineral from which one or more metals can be profitably extracted.
2. What is metallurgy? 
Ans: Metallurgy is the science of extracting metals from their ores and purifying them.
3. Differentiate between metal and non–metals on the basis of any one physical
Ans: Metals are ductile. It is the property that allows the metals to be drawn into wires.
Non metals are not ductile.
4. Give the reaction of magnesium with water. 
Ans: Mg + 2H2O -----------> Mg(OH)2 + H2
5. What is alloy? 
Ans: An alloy is a homogeneous mixture of a metal with another metal(s) or non–metal(s).
6. Define: (i) Concentration of ore (ii) Reduction 
(i) Concentration of ore: It is the preliminary treatment of an ore in which impurities are removed.
(ii) Reduction: The metal compound is reduced to get free metal
7. What is metallic luster? Why metals are useful for jewellery and decoration. 
Ans: Metals have shiny appearance. This property is known as metallic luster.The shiny appearance makes the metals useful for jewellery and decoration
8. Explain conductivity in case of metals and non metals. 
Ans: Metals are good conductor of heat and electricity. Gold is the best conductor followed by silver, copper and aluminum.
Non–metals are generally bad conductors of heat and electricity.
9. Discuss the reaction of metals and non–metals with oxygen. 
Ans: In general, metals form oxides on combining with oxygen. The water solutions of these oxide are alkaline or basic in nature and changes red litmus into blue.
2Mg + O2 ---------> 2MgO
MgO + H2O-----> Mg (OH)2
Non metals too combine with oxygen to form oxides.
However, such oxides are acidic in nature
10. Discuss the reaction of metals with water. 
Ans: Sodium reacts violently with water. Magnesium reacts mildly with cold water but
vigorously with hot water or steam.
Mg + 2H2O -----------> Mg(OH)2 + H2
Zinc and iron react very mildly with steam, whereas copper, silver and nickel do not
react with water.Non–metals also do not react with water.
11. What happens when iron nails are put in copper sulphate solution? 
Ans: When iron nails are put in copper sulphate solution, the blue colour of the solution
gradually. At the same time, iron nails get a shiny coating of red brown copper metal on
their surface.This change takes place as iron displaces copper from copper sulphate.
12. What is electroplating? 
Ans: Electroplating: Iron and steel are protected from corrosion by coating them with a
layer of tin or chromium metals which are resistant to corrosion. This can be done by electroplating. A thin layer of tin deposited on the inner surface of iron containers makes them safe, for storing food.
Chromium plating protects steel furniture, taps and bicycle handles from corrosion. Coating of chromium not only giveslonger life to the coated objects but also gives a good shining appearance to them.
13. Discuss some common uses of metals and non–metals? 
Ans: Metals are strong, hard and rigid. So they are used in making machinery.
The automobiles, the aeroplanes, the trains, satellites, industrial gadgets all use metals in large amounts.
Iron is the most commonly used metal.
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