In order to compact the periodic table, the lanthanides and actinides are often shown as a separate little "island" underneath the main body of the table analogous to maps of the United States which show Alaska and Hawaii floating off the coast of California. For a look at the periodic table with these elements incorporate into the main table, see here.
The inner transition elements are sometimes called the f -block elements , since in this region the f -orbitals are being filled in. The lanthanides except for the synthetic element promethium , along with scandium Sc and yttrium Y are sometimes referred to as "rare earth elements" or "rare earth metals" or just "rare earths". Many high-quality pots and pans are made with copper bottoms, which distributes the heat from the stovetop quickly and evenly throughout the pan. Because copper resists corrosion by water, air, and most acids except for concentrated nitric and sulfuric acids , it is ideal for making coins.
The US one-cent piece, the penny, used to be made from solid copper or copper alloyed with tin, nickel, or zinc but due to the increasing cost of copper, this was replaced in with a coin made from a zinc core surrounded by a thin copper plating about 2.
The US Sacajawea dollar coin, first issued in November of is also made primarily of copper Copper is also widely used in plumbing and water pipelines, motors and generators, circuitry and computer chips, household fixtures, kitchen utensils, dinnerware such as sterling silver, which consists of silver alloyed with 7.
Copper is also widely used in statuary. The Statue of Liberty is made of The Colossus of Rhodes, one of the Seven Wonders of the Ancient World, was a foot bronze statue of the Greek god Helios on the island of Rhodes which stood at the mouth of the Mandraki harbor entrance; it was completed in BC and destroyed by an earthquake in BC.
Copper is used to make several important metal alloys. Bronze is an alloy of copper and tin. Brass is an alloy of copper and zinc, which is addition to being harder than copper can be polished to a high, golden luster. Gunmetal also known as red brass is an alloy of copper, tin, and zinc which is strong enough to make guns and cannons. Cupronickel also called Monel metal is an alloy of copper and nickel commonly used in coins, such as the US 5-cent piece, and in shipbuilding.
Alloys of copper and nickel are also used in desalination plants and underwater pumps because it resists corrosion by sea water. This material, sometimes called blue vitrol, is used in fungicides and algicides, and in ink pigments.
Copper II chloride, CuCl 2 , is used as a dye fixer in the textile industry. Copper II acetate, Cu C 2 H 3 O 2 2 , also known as verdigris, forms as copper is exposed to air and seawater over long periods of time; it is widely used as a green pigment in oil paintings.
Copper is essential in the diet because it is a part of several enzymes in the body, such as cyctochrome c oxidase, which is required for energy production. Copper is plentiful in foods such as seafood especially shellfish , lamb, duck, pork, and beef, almonds, walnuts, Brazil nuts, sunflower seeds, mushrooms, and bran. The minimum amount of copper needed in the diet is around 1. Some mollusks such as oysters and some arthropods such as the horseshoe crab use hemocyanin to carry oxygen to their cells.
In this protein complex, a copper I ion is held in place by histidine groups; molecular oxygen complexes with the copper ion to form a blue copper II -oxygen complex.
In Star Trek , Vulcan blood was green because it was copper-based. Silver is a soft, ductile, malleable, silvery duh metal. The name is derived from the Anglo-Saxon word for the metal, siolfur ; its chemical symbol, Ag, is derived from the Latin name for silver, argentum.
Silver is a fairly rare element, having a concentration of 70 ppb in the Earth's crust, making it the 66th most abundant element. However, most silver is obtained as a by-product from the refining of other metals. Silver was known in many ancient civilizations, but since is not obtained from the ground as the pure metal, it has not been used for as long as gold has been.
Silver was first mined around BC, and was extensively used in coins, although silver coins are too soft to be very durable. Silver is the metal which is most conductive to electricity and heat, which makes is extremely important in the electronics industry. The metal is extremely malleable and ductile — one gram of silver can be drawn into a wire nearly two kilometers long.
Silver is is stable to water and oxygen, but forms silver sulfide, Ag 2 S, when it is exposed to sulfur compounds in the air; this forms a black coating tarnish on the silver, which requires regular cleaning. Silver is considered one of the precious metals because of its rarity, stability, high melting point, and high luster. Silver is widely used in the electronics industry in switches, circuits, and electronic devices such as computer keyboards.
It is also used in cutlery, jewelry, and mirrors. Amalgams of silver, tin, and mercury are used by dentists to fill cavities. Silver iodide is used in used to seed clouds to encourage rainfall. Colloidal silver is a suspension of silver used in "alternative" medicine as a antibiotic. However, prolonged use, or overdoses, of colloidal silver can lead to a condition called argyria , in which silver becomes deposited in tissues throughout the body, causing the skin to become bluish-gray.
Although this is not harmful in itself, it is disfiguring, and it may not be possible to reverse the condition. Gold is a soft, malleable, yellow metal. It is an extremely rare element, having a concentration of 1 ppb in the Earth's crust, making it the 73rd most abundant element.
The name is derived from the Anglo-Saxon language, while the chemical symbol "Au" is derived from the Latin name for the metal, aurum "shining dawn". It is often found as the free element as nuggets or grains, and in alluvial deposits, and is associated with some sulfide ores, and is also found in the mineral sylvanite [silver gold telluride, Ag,Au Te 2 ].
Gold has been used by humans for thousands of years. The desire for gold encouraged the ancient alchemists to try to figure out how to make the "Philosopher's Stone" that would enable them to transmute base metals such as lead into gold.
Rowling , they did accumulate a lot of empirical observations that led to the development of the science of chemistry. Gold is extremely unreactive: the only acids that dissolve gold are aqua regia "king of waters," a mixture of concentrated hydrochloric acid and nitric acid , and selenic acid, H 2 SeO 4. Gold extremely malleable and ductile: one gram of gold can be beaten out to make a thin film that is one square meter in area and 50 nanometers in thickness.
Gold is also a very good electrical conductor, making it useful in electrical connections. The oceans contain roughly 10 million tons of gold, but it is at such a low concentration — about 10 parts per thousand — that is impractical to try to extract it. Like silver, gold is considered one of the precious metals because of its rarity and stability. Thin films of gold are used in some large buildings to reflect away heat; the Mylar film that coats the skins of some spacecraft is also covered in gold foil for the same reason.
The purity of gold is measured in units called karats. Pure gold is 24 karat. Gold in jewelry is often alloyed with silver or copper, with a small amount of zinc to harden it. Gold salts are used in some treatments for arthritis, when non-steroidal anti-inflammatory drugs do not work. Because there are side effects from having gold build up in the body, this kind of treatment can only be used for a few years. Gold is also used in dentistry to fill cavities and make crowns; the gold is alloyed with silver, palladium, and zinc to harden the amalgam.
Over 60 tons of gold per year are used in this fashion. Roentgenium is a synthetic element, produced by the bombardment of bismuth with nickel The longest-lived isotope, roentgenium, has a half-life of 3. Zinc is a fairly hard, bluish-white metal. The name is derived from the German word for the metal, zink , which may in turn have originated from the Persian word for stone, sing. It is found in the Earth's crust at a concentration of 75 ppm, making it the 24th most abundant element.
Zinc compounds were known for many thousands of years, and were used in medical treatments. Zinc metal was refined in India as far back as BC, and was used in making brass by mixing copper with zinc ores such as calamine, but it was not recognized as an element until the mid's.
Zinc tarnishes in the air to form a coating of zinc oxide. Zinc is the fourth most commonly used metal, after iron, aluminum, and copper.
Its main use is used to coat "galvanize" iron or steel, forming a protective layer which is preferentially oxidized instead of the iron. Since , the US one-cent piece has been made of primarily zinc about Zinc forms the anode component of dry cell and alkaline batteries; although they are not rechargeable, they are still commonly used because they are cheap. Zinc oxide, ZnO, is a white, insoluble powder used in white paints and watercolors, and pharmaceutical ointments, such as diaper rash medications and calamine lotion, a mixture of zinc and iron oxides.
Zinc oxide is used in some sunscreens and sunblocks to protect the skin against damaging UV-B rays. Zinc sulfide, ZnS, is used as a white pigment in fluorescent paints, and is combined with barium sulfide to make a white pigment called lithophone; it is also used in scintillation detectors because it emits light when excited by X-rays or electrons.
Zinc dichromate, ZnCr 2 O 7 , is an orange-red pigment. Zinc chromate, ZnCrO 4 , is a brilliant yellow pigment. Zinc is non-toxic, and is an essential nutrient in the diet, because it is used in many proteins and enzymes in the body. A particularly important one is carbonic anhydrase, which is responsible for the transport of carbon dioxide in vertebrates.
Foods that are rich in zinc include oysters, red meat, herring, beans, nuts, cheeses, whole grain and whole grain breads, sunflower and pumpkin seeds, maple syrup, and bran. Cadmium is a soft, malleable, silvery metal.
It names comes from the Greek word cadmia , the ancient Greek name for calamine, a mineral of zinc carbonate ZnCO 3 ; cadmium was first observed as an impurity in some calamine ores. It is found in the ores greenockite [cadmium sulfide, CdS], cadmoselite [cadmium selenide, CdSe], and otavite [cadmium carbonate, CdCO 3 ], but it is usually obtained as a by-product from the mining of zinc ores. Cadmium is used for electroplating steel, which is especially useful in preventing corrosion in ocean-going vessels, and in the manufacture of bearings.
It main use in nickel-cadmium NiCad batteries, where it serves as the anode see also the entry for Nickel above. Cadmium can absorb neutrons, and is used in the control rods that regulate nuclear reactions in fission power plants. Cadmium compounds are used in paint pigments to produce a wide variety of intense colors, such as cadmium yellow cadmium sulfide, CdS and cadmium red cadmium selenide, CdSe.
Small amounts of cadmium are can be eliminated by the body, but it can accumulate in the liver and kidneys. Exposure to large amounts of cadmium is toxic, in part because it interferes with the action of zinc-containing enzymes. Mercury is a very dense, heavy, silver-white metal that is a liquid at room temperature. Mercury is also known as "quicksilver. In many respect, mercury is an unusual metal.
It is the only commonly encountered metal that is a liquid at room temperature, having a melting point of When frozen, mercury looks and feels like lead. It has a boiling point of It also has a very high density, of Mercury is a poor conductor of heat, but a good conductor of electricity. It has a high coefficient of expansion, and expands and contracts even with changes in temperature.
This, combined with the fact that it does not adhere to glass much, makes mercury an ideal liquid for measuring devices such as thermometers, barometers, and sphygmomanometers blood-pressure meters. Mercury forms alloys with a number of metals; these are usually referred to as amalgams. Mercury compounds, in the form of cinnabar and other ores, have been used for thousands of years.
Metallic mercury has been known since at least BC. Some alchemists believed that mercury was the key to figuring out how to transform base metals into gold, but these investigations proved fruitless at least from the perspective of actually making gold. Mercury, in the form of mercury II oxide, MgO, is used in small zinc-mercury "button" batteries that are used in hearing aids and other small devices. Anne Marie Helmenstine, Ph. Chemistry Expert. Helmenstine holds a Ph. She has taught science courses at the high school, college, and graduate levels.
Facebook Facebook Twitter Twitter. Updated December 03, Featured Video. Cite this Article Format. Helmenstine, Anne Marie, Ph. Transition Metals: List and Properties. Titanium is purple in colour. The reason why transition metal in particular are colorful is because they have unfilled or either half filled d orbitals. There is Crystal field theory which explains the splitting of the d orbital, which splits the d orbital to a higher and lower orbital. Coordination compounds of transition metals with weak-field ligands are often blue-green, blue, or indigo because they absorb lower-energy yellow, orange, or red light.
Each of these complex ions has the same metal with the same oxidation state, so the ligand field is the relavant factors. Transition metals and their compounds are often good catalysts. Transition metals and their compounds function as catalysts either because of their ability to change oxidation state or, in the case of the metals, to adsorb other substances on to their surface and activate them in the process. Transition elements are defined as elements that form at least one ion that contains partially filled d orbitals.
The electronic configuration for a zinc atom is 1s2, 2s2, 2p6, 3s2, 3p6, 4s2, 3d As none of the d orbitals are partially, zinc cannot be classified as an transition element. A transition metal is one that forms one or more stable ions which have incompletely filled d orbitals.
On the basis of this definition, scandium and zinc do not count as transition metals — even though they are members of the d block. The d-block elements are called transition elements because they exhibit transitional behaviour between s-block and p-block elements.
Their properties are transitional between highly reactive metallic elements of s-block which are ionic in nature and the elements of p-block which are covalent in nature. When visible light falls on a transition metal compound or ion, the unpaired electrons present in the lower energe d-orbital get promoted to high energy d-orbitals, called d-d transition, due to the absorption of visible light.
Therefore, transmitted light shows some colour complementary to the absorbed colour.
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