Answer the following question:-
P.S = Please solve all the following questions.
Answers
Answer:
que 1Answer: Metals react with the atmosphere oxygen and the oxygen is bonded to them. after a layer of oxide forms over the surface, the metals lose their lustre. this does not happen in case of metals like Platinum and gold as it is difficult to oxidise them
que2 The lower the level of resistivity, the more electrical conductivity a metal has. Copper has low resistivity, and therefore is an excellent conductor. Copper is also less oxidative than other metals
que3Iron is used to make water boilers for factorieIn factories cast iron are used to make water heaters and water boilers because at factories they need boilers to produce hot water and not steam, Iron boilers run at low pressure and they keep heating the water and they avoid boiling
que4 When zinc is added to copper sulphate (CUSO4) solution due to more reactivity of zinc, cooper is replaced by the zinc and forms zinc sulphate. During the process, the⁰0 colour of the solution changes from blue to colourless.
que5When copper is dipped in silver nitrate , copper being more reactive than silver, displaces silver from it's solution to form copper nitrate. Explanation: Cu + AgNO3 -------> Cu(NO3)2 + Ag
que6The two main users of the sonorous metals is their use to make musical instruments such as metal phones, steel drums or triangles since their property is to see create a ringing sound. The sonorous metals as the one that gives out the sound on coming in contact with another object.
que7Take three test tubes A, B and C and place one clean iron nail in each of them. In the test tube A pour some water and close its mouth with the help of a cork. In the test tube B pour boiled water which does not contain dissolved air. Also pour some oil in test tube B to form a layer over boiled water. The layer of oil will prevent the entry of air in water. In the test tube C put some anhydrous calcium chloride and cork it. Anhydrous calcium chloride is drying agent. So, it is added into test tube C to absorb all the moisture present in the air of test tube. Keep these test tubes undisturbed for some days.
After some days, you will observe that the nail in test tube B does not rust because the nail was exposed only to water and no air was present in it. In the same way the nail present in test tube C does not rust because in this tube air is dry and water is not present. But the nail present in test tube A rusts because in test tube A the nail was exposed to both air and water.
This shows that for rusting of iron
que8Galvanisation or galvanization (or galvanizing as it is most commonly called) is the process of applying a protective zinc coating to iron or steel, to prevent rusting. The most common method is hot dip galvanizing, in which steel sections are submerged in a bath of molten zinc.Galvanization' was a term used during the 19th century to describe the administration of electric shocks. In 1836, Sorel in France took out the first of numerous patents for a process of coating steel by dipping it in molten zinc after first cleaning it. He provided the process with its name 'galvanizing'.
que9Metals can be distinguished from non-metals on the basis of their physical and chemical properties. Recall that lustre and hardness are physical properties.You are familiar with a number of materials like iron, aluminium, copper, etc. Some materials have been given in Table. Metals are used in making machinery, automobiles, aeroplanes, buildings, trains, satellites, gadgets, cooking utensils, water boilers, etc.
Metals are lustrous whereas non-metals have no lustre.
Generally, metals are malleable and ductile. Non-metals do not have these properties.
Generally, metals are good conductors of heat and electricity but non-metals are poor conductors.
On burning, metals react with oxygen to produce metal oxides which are basic in nature. Non-metals react with oxygen to produce non- metallic oxides which are acidic in nature.
Some metals react with water to produce metal hydroxides and hydrogen gas. Generally, non- metals do not react with water.
Metals react with acids and produce metal salts and hydrogen gas. Generally, non-metals do not react with acids.
Some metals react with bases to produce hydrogen gas.
More reactive metals displace less reactive metals from their compounds in aqueous solutions.
Metals and non-metals are used widely in every day life.
