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Chemistry - Zinc Introduction In the periodic table, zinc is the first element of group 12. The symbol of zinc is  ‘Zn’  and the atomic number is  ‘30.’ In terms of availability, zinc is the 24 th  most abundant element found in the Earth's crust and it has five stable isotopes. The most common zinc ore is sphalerite (zinc blende), which is a zinc sulfide mineral. Andreas Sigismund Marggraf, the German chemist, first discovered the pure metallic zinc in 1746. Interestingly, alchemists burned zinc in the air and form something different thing and they named that  "philosopher's wool"  or " white snow ." Salient Features of Zinc Zinc’s color is bluish-white and it is lustrous and diamagnetic metal. Zinc metal is normally hard and brittle; however, at when the temperature increases from 100 0 C, it becomes malleable. When temperature increases 210 0 C, then the zinc metal again becomes brittle and can be pulverized easily by beating. Zinc is a conductor of ele...

Chemistry - Platinum Introduction Platinum is a malleable, ductile, dense, and highly unreactive chemical element. The symbol of platinum is  ‘Pt’  and its atomic number is  ‘78.’ The name of platinum is derived from a Spanish term i.e. ‘platina,’ which means " little silver ." Platinum is the most precious and the rarest metal (element) on the earth. Salient Features of Platinum Following are the important features of the platinum − Platinum is a silver white metal. Platinum is an element of group 10 of the periodic table. Platinum is one of the rarest elements in the crust of the earth. Platinum is one of the least reactive elements. Platinum has six natural isotopes. Platinum is one of the most highly valuable and precious metals. Platinum is characteristically resists corrosion in all conditions. Because of this reason, it is considered as noble metal. Platinum is normally insoluble in nitric and hydrochloric acid, but dissolves in hot  aqua regia . After dissolv...

Chemistry - Silver Introduction Silver is a soft, lustrous transition, and white metal. Silver has the highest electrical and thermal conductivity; and, it has also the highest reflectivity of any metal. The symbol of silver is  ‘Ag’  and atomic number is  ’47.’ Salient Features of Silver Silver is a precious metal used since long time by human beings. Silver is an element of group 11 of the periodic table. Silver has an excellent white metallic luster commonly used in a high polish. As silver has no color; therefore, it has high reflectivity (of light). Silver has very high electrical and thermal conductivity. Its electric conductivity is the highest – higher than copper. Among all the metals, silver also has the lowest contact resistance. Occurrence of Silver The metal silver is usually found in the Earth's crust in the pure form. Silver also found as an alloy with the gold and some other metals. Silver is also found in some minerals, such as argentite and chlorargyrite...

Chemistry - Gold Introduction Gold is a bright, reddish yellow, soft, dense, malleable, and ductile metal naturally found in the earth’s crust. The symbol of gold is  ‘Au’  and atomic number is  ‘79.’ Gold is (chemically) a transition metal and belongs to group 11 of the periodic table. Salient Features of Gold Gold, which remains in a solid state under standard conditions, is the least reactive element. Gold is resistant to most of the acids. Gold does dissolve in aqua regia; aqua regia is a mixture of nitric acid and hydrochloric acid. However, gold is insoluble in nitric acid. Gold usually dissolves in alkaline solutions of cyanide. Cyanide solutions are commonly used in mining and electroplating. Gold also dissolves in mercury and forms  ‘amalgam alloys.’ Gold does not react with oxygen at any temperature. Occurrence of Gold Gold commonly occurs as a free element i.e. in the natural form. Gold occurs as nuggets or else found in in rocks, grains, in veins, and in ...

Chemistry - Copper Introduction Copper is a soft, ductile, and malleable metal. Copper has very high thermal and electrical conductivity. The symbol of copper is  ‘Cu’  and atomic number is  ’29.’ Copper is known to people since (about) c. 8000 BC. Copper is the first metal, which was smelted from its ore around c. 5000 BC. Salient Features of Copper Copper was the first metal that cast into a shape (in a mold). Copper was the first metal that successful alloyed with another metal, e.g. copper alloyed with tin and resultantly bronze is prepared. It is done about c. 3500 BC. First metal to be purposefully alloyed with another metal, tin, to create bronze, c. 3500 BC. Copper has a natural reddish-orange color; it is visible once the its surface is exposed. Copper is a very good conductor of electricity and heat. Copper is an element of group 11 of the periodic table. Copper normally does not react with water; however, it does react slowly with atmospheric oxygen and form a ...

Chemistry - Iron Introduction Iron is the most common element found in largely in outer as well inner core of the earth. The symbol of iron is  ‘Fe’  and atomic number is  ‘26.’ Iron is one of the earliest known elements that is being used by human beings. Salient Features of Iron Following are the major features of iron − Pure iron element is soft, ductile, and malleable. The boiling point of iron ranges between 1533 0 C and 2450 0 C. Iron easily gets attracted towards magnet. In dry air, iron remains inactive and does not react (with air); however, in moist air, it reacts and forms rust. Pure iron normally does not react with pure water; however, it reacts easily with ordinary of polluted water and rust forms. Iron reacts with halogen and Sulphur to form halide and sulphide accordingly. Occurrence of Iron The inner and outer cores of the earth are largely made up of iron and nickel. Most likely, iron is the most abundantly available element of the earth; however, it is ...

Chemistry - Maganese Introduction Manganese is a chemical element that usually found in combination with the iron. The symbol of manganese is  ‘Mn’  and atomic number is  ’25.’ Manganese is a metal very important for the industrial use. In 1774, Johan Gottlieb Gahn, first time isolated an impure sample of manganese metal in 1774. Features of Manganese Following are the major features and characteristics of manganese − Similar to iron, manganese is silvery-gray metal. Manganese can be oxidized easily, but very difficult to fuse it, as it is very hard and brittle. In air, manganese gets tarnished slowly (oxidization). Manganese is an element, which is part of the iron group. Occurrence of Manganese Manganese is the 12 th  most abundant element of the earth’s crust. Soil usually contains about 7–9000 ppm of manganese with an average of 440 ppm. Seawater has only about 10 ppm manganese; whereas, the atmosphere contains about 0.01 µg/m3. Pyrolusite (MnO 2 ) is the most im...

Chemistry - Magnesium Introduction Magnesium is a shiny gray solid element. The symbol of magnesium is  ‘Mg’  and atomic number is  ‘12.’ With approximately 80% of the world market share, China is the largest supplier of magnesium. Salient Features of Magnesium The density of magnesium is two-thirds the density of aluminum. Among all the alkali metals of the Earth, magnesium has lowest melting point (i.e. about 1,202 0 F) and lowest boiling point (about 1,994 0 F). Magnesium usually reacts with water at room temperature. Sometimes, magnesium is also used as an igniter for thermite. Magnesium, when burns in air, produces a brilliant-white light, which also includes strong ultraviolet wavelengths. Magnesium, when burns, it produces intense bright and white light (see image given above). Occurrence of Magnesium By mass, magnesium is the eighth-most-abundant element found in the Earth's crust. Magnesium is found usually in large deposits of magnesite, dolomite, and other such...

Chemistry - Metallurgy The branch of science and technology that studies the properties of metals and their production and purification is known as  metallurgy . Naturally occurring solid inorganic substance is known as a  mineral . Naturally occurring solid material from which valuable mineral or metal can be extracted is known as  ore . The following table illustrates the major elements and their ores − Element Ores Chemical Composition Aluminum Bauxite Al 2 O 3 2H 2 O Corundum Al 2 O 3 Kryolite Na 3 AlF 6 Dyspore Al 2 O 3 .H 2 O Copper Copper Pyrite CuFeS 2 Malachite 2CuCO 3 Cu(OH) 2 Iron Hematite Fe 2 O 3 Magnetite Fe 3 O 4 Siderite FeCO 3 Sodium Sodium Carbonate Na 2 CO 3 Sodium Chloride NaCl Sodium Nitrate NaNO 3 Sodium Sulphate Na 2 SO 4 Potassium Potassium Chloride KCl Potassium Carbonate K 2 CO 3 Potassium Nitrate KNO 3 Magnesium Magnesite MgCO 3 Dolomite CaMg(CO 3 ) 2 Epsom Salt MgSO 4 Calcium Calcium Carbonate CaCO 3 Tin Cassiterite SnO 2 Lead Galena PbS Ceruss...