🗊Презентация Metals

Reactivity series of metals The arranging of metals in the decreasing order of their reactivity is called reactivity series of metals: K - Potassium Na - Sodium Most Ca - Calcium reactive Mg - Magnesium Al - Aluminium Zn - Zinc Reactivity Fe - Iron decreases Pb - Lead H - Hydrogen Cu - Copper Hg - Mercury Least Ag - Silver reactive Au - Gold

Reaction of metals with water

Explaining displacement reactions

Displacement reaction Zinc displaces copper from copper sulfate solution: Zn + CuSO4 ZnSO4 + Cu Iron displaces copper from copper (II) sulfate: Fe + CuSO4 FeSO4 + Cu

Occurrence of metals : Some metals like gold, silver, platinum etc are found in the free state (nugget) in the earth’s crust because they are least reactive. Most metals are found as oxides, carbonates, sulfides, halides etc. Minerals: are elements or compounds which occur naturally inside the earth’s crust. Ore: is a mineral from which metals can be extracted profitably. Gangue: is the impurities present in the ore like rock particles, sand particles, clay particles etc.

Ways of Metal Extraction Potassium K Sodium Na Calcium Ca Magnesium Mg Aluminium Al Zinc Zn Iron Fe Tin Sn Lead Pb Copper Cu Mercury Hg Silver Ag Gold Au Platinum Pt

Steps involved in the extraction of metals from their ores Metals of Metals of Metals of high reactivity medium reactivity low reactivity Electrolysis of molten ore Carbonate ore Sulfide ore Sulfide ore Pure metal Calcination Roasting Roasting Oxide of metal Metal Reduction to metal Refining Refining

Using of Metals Using of Metals Metal used in manufacturing are usually alloys, which are composed of two or more elements, with at least one being metallic element. Metals can be divided into two basic categories: Ferrous Non ferrous Alloys are stronger and harder than pure metals and they also can with stand corrosion better. Pure metals are relatively a little softer (but they are still hard) and they have a low resistance to corrosion as they are affected by air and water easily. Hence alloys are used more often instead of pure metals. Nowadays, complex alloys have been made with specific desired properties. Usually, transition metals are used in the production of alloys.

Ferrous Metals (black): Ferrous Metals (black): Ferrous metals are based on iron: the group includes steel and cast iron. Pure iron has limited commercial use, but when alloyed with carbon. Iron has more uses and greater commercial value than any other metal. Non ferrous (colored): They include the other metallic elements and their alloys. They include metals and alloys of aluminum, copper, gold, silver and other metals.

METALS ALLOYS An alloy is a homogeneous mixture of a metal with other metals or non metal: Steel and cast iron – iron, carbon Stainless steel – iron, carbon, cobalt, nickel Brass – copper, zinc Bronze – copper, tin Solder – Lead, tin (used for welding electrical wires together) If one of the metals in an alloy is mercury, it is called an amalgam.