260 likes | 421 Views
Periodic Table Powerpoint. Hydrogen. Hydrogen is the lightest element. It is by far the most abundant element in the universe and makes up about 90 % of the universe by weight. Hydrogen as water (H2O) is absolutely essential to life and it is present in all organic compounds. Lithium.
E N D
Hydrogen Hydrogen is the lightest element. It is by far the most abundant element in the universe and makes up about 90% of the universe by weight. Hydrogen as water (H2O) is absolutely essential to life and it is present in all organic compounds.
Lithium Lithium is a Group 1 (IA) element containing just a single valence electron (1s22s1). Group 1 elements are called "alkali metals". Lithium is a solid only about half as dense as water and lithium metal is the least dense metal.
Sodium Sodium is a Group 1 element (or IA in older labeling styles). Group 1 elements are often referred to as the "alkali metals". The chemistry of sodium is dominated by the +1 ion Na+. Sodium salts impart a characteristic orange/yellow color to flames and orange street lighting is orange because of the presence of sodium in the lamp.
Potassium Potassium is a metal and is the seventh most abundant and makes up about 1.5 % by weight of the earth's crust. Potassium is an essential constituent for plant growth and it is found in most soils. It is also a vital element in the human diet.
Rubidium Rubidium can be liquid at ambient temperature, but only on a hot day given that its melting point is about 40°C. It is a soft, silvery-white metallic element of the alkali metals group (Group 1). It is one of the most electropositive and alkaline elements. It ignites spontaneously in air and reacts violently with water, setting fire to the liberated hydrogen. As so with all the other alkali metals, it forms amalgams with mercury. It alloys with gold, cesium, sodium, and potassium. It colors a flame yellowish-violet.
Cesium The metal is characterized by a spectrum containing two bright lines in the blue (accounting for its name). It is silvery gold, soft, and ductile. It is the most electropositive and most alkaline element. Cesium, gallium, and mercury are the only three metals that are liquid at or around room temperature. Cesium reacts explosively with cold water, and reacts with ice at temperatures above -116°C. Cesium hydroxide is a strong base and attacks glass.
Francium Francium occurs as a result of α disintegration of actinium. Francium is found in uranium minerals, and can be made artificially by bombarding thorium with protons. It is the most unstable of the first 101 elements. The longest lived isotope, 223Fr, a daughter of 227Ac, has a half-life of 22 minutes. This is the only isotope of francium occurring in nature, but at most there is only 20-30 g of the element present in the earth's crust at any one time. No weighable quantity of the element has been prepared or isolated. There are about 20 known isotopes.
Beryllium Beryllium is a Group 2 (IIA) element. It is a metal and has a high melting point. At ordinary temperatures, beryllium resists oxidation in air. Beryllium compounds are very toxic. Its ability to scratch glass is probably due to the formation of a thin layer of the oxide. Aquamarine and emerald are precious forms of the mineral beryl, [Be3Al2(SiO3)6].
Magnesium Magnesium is a grayish-white, fairly tough metal. Magnesium is the eighth most abundant element in the earth's crust although not found in it's elemental form. It is a Group 2 element (Group IIA in older labeling schemes). Group 2 elements are called alkaline earth metals. Magnesium metal burns with a very bright light.
Calcium Calcium as the element is a grey silvery metal. The metal is rather hard. Calcium is an essential constituent of leaves, bones, teeth, and shells. Calcium is the fifth most abundant element in the earth's crust and makes up more than 3% of the crust. Calcium does not occur as the metal itself in nature and instead is found in various minerals including as limestone, gypsum and fluorite. Stalagmites and stalactites contain calcium carbonate (CaCO3). Calcium carbonate is the basis of the cement industry.
Strontium Strontium does not occur as the free element. Strontium is softer than calcium and decomposes water more vigorously. Freshly cut strontium has a silvery appearance, but rapidly turns a yellowish color with the formation of the oxide. The finely divided metal ignites spontaneously in air. Volatile strontium salts impart an excellent crimson color to flames, and these salts are used in pyrotechnics.
Barium Barium is a metallic element, soft, and when pure is silvery white like lead. The metal oxidizes very easily and it reacts with water or alcohol. Barium is one of the alkaline-earth metals. Small amounts of barium compounds are used in paints and glasses.
Radium Pure metallic radium is brilliant white when freshly prepared, but blackens on exposure to air, probably due to formation of the nitride. It exhibits luminescence, as do its salts; it decomposes in water and is somewhat more volatile than barium. Radium imparts a carmine red color to a flame.
Scandium Scandium is a silvery-white metal which develops a slightly yellowish or pinkish cast upon exposure to air. It is relatively soft, and resembles yttrium and the rare-earth metals more than it resembles aluminum or titanium. Scandium reacts rapidly with many acids. Scandium is apparently a much more abundant element in the sun and certain stars than on earth.
Yttrium Yttrium has a silvery-metallic luster. Yttrium turnings ignite in air. Yttrium is found in most rare-earth minerals. Moon rocks contain yttrium and yttrium is used as a "phosphor" to produce the red color in television screens.
Lutetium Pure metallic lutetium has been isolated only in recent years and is one of the more difficult to prepare. It can be prepared by the reduction of anhydrous LuCl3 or LuF3 by an alkali or alkaline earth metal.
Lawrencium Lawrencium is a synthetic "rare earth metal" which does not occur in the environment
Titanium Titanium s a lustrous, white metal when pure. Titanium minerals are quite common. The metal has a low density, good strength, is easily fabricated, and has excellent corrosion resistance. The metal burns in air and is the only element that burns in nitrogen. It is marvelous in fireworks.
Zirconium Zirconium is a greyish-white lustrous metal. The finely divided metal can ignite spontaneously in air, especially at elevated temperatures. The solid metal is much more difficult to ignite. The inherent toxicity of zirconium compounds is low. Hafnium is invariably found in zirconium ores, and the separation is difficult. Commercial grade zirconium contains from 1 to 3% hafnium. The hafnium is removed from the zirconium used in the nuclear power industry.
Hafnium Most zirconium minerals contain 1 to 3% hafnium. Hafnium is a ductile metal with a brilliant silver luster. Its properties are influenced considerably by the impurities of zirconium present. Of all the elements, zirconium and hafnium are two of the most difficult to separate. Hafnium is a Group 4 transition element.
Rutherfordium Rutherfordium is a synthetic element that is not present in the environment at all. It has no uses.
Vanadium Pure vanadium is a greyish silvery metal, and is soft and ductile. It has good corrosion resistance to alkalis, sulphericacid, hydrochloric acid, and salt waters. The metal oxidizes readily above 660°C to form V2O5. Industrially, most vanadium produced is used as an additive to improve steels.
Niobium The name niobium was adopted officially by IUPAC in 1950, but a few commercial producers still like to refer to it as columbium. Niobium is a shiny, white, soft, and ductile metal, and takes on a bluish tingewhen exposed to air at room temperatures for a long time. The metal starts to oxidize in air at high temperatures, and when handled hot must be done so under a protective atmosphere so as to minimize oxide production.
Tantalum Tantalum is a greyish silver, heavy, and very hard metal. When pure, it is ductile and can be drawn into fine wire, which can be used as a filament for evaporating metals such as aluminum. Tantalum is almost completely immune to chemical attack at temperatures below 150°C, and is attacked only by hydrofluoric acid, acidic solutions containing the fluoride ion, and free sulfur trioxide. The element has a melting point exceeded only by tungsten and rhenium.
Dubnium Dubnium is a synthetic element that is not present in the environment at all. It has no uses.