HYDROGEN Essays - Chemistry, Nature, Matter, Chemical Elements

HYDROGEN Hydrogen, symbol H, is reactive, colorless, odorless, and tasteless gaseous element. The atomic number of hydrogen is 1. The element is usually classed in group 1 of the periodic table. Hydrogen was confused with other gases until the a British chemist demonstrated in 1766 that it was evolved by the action of sulfuric acid on metals and also showed at a later date that it was an independent substance that combined with oxygen to form water. The British chemist Joseph Priestley named the gas "inflammable air" in 1781, and the French chemist Antoine Laurent Lavoisier renamed it hydrogen. Like most gaseous elements, hydrogen is diatomic, but it becomes and turns into free atoms at high temperatures. Hydrogen has a lower boiling point and melting point than any other substance except helium. When allowed to evaporate rapidly under reduced pressure, it freezes into a colorless solid. Hydrogen is a mixture of two different forms, orthohydrogen and parahydrogen, ordinary hydrogen containing about three-fourths of the ortho form and one-fourth of the para form. The melting point and boiling point of the two forms differ slightly from those of ordinary hydrogen. Hydrogen is known to exist in three isotopic forms. The nucleus of each atom of ordinary hydrogen is composed of one proton. Deuterium, present in ordinary hydrogen to the extent of 0.02 percent, contains one proton and one neutron in the nucleus of each atom and has an atomic mass of two. Tritium, an unstable, radioactive isotope, contains one proton and two neutrons in the nucleus of each atom, and has an atomic mass of three. Free hydrogen is found only in very small traces in the atmosphere, but solar and stellar spectra show that it is abundant in the sun and other stars, and is, in fact, the most common element in the universe. In combination with other elements it is widely distributed on the earth, where the most important and abundant compound of hydrogen is water, H2O. It is a component of all the constituents of living matter as well as of many minerals. It forms an essential part of all hydrocarbons and a vast variety of other organic substances. All acids contain hydrogen. Hydrogen reacts with many nonmetals. The reaction of oxygen and hydrogen takes place at room temperature only in the presence of a catalyst such as finely divided platinum. When hydrogen is mixed with air or oxygen and ignited, the mixture explodes. Hydrogen also combines with some metals, such as sodium and lithium, to form hydrides. It acts as a reducing agent on metallic oxides. Hydrogen is prepared in the laboratory by the action of dilute acid on metals, such as zinc, and by the electrolysis of water. Large quantities of the gas are produced industrially from various fuel gases. Hydrogen is separated from water gas, natural gas, either by liquefaction of the other components of the gas or by catalytic conversion of the carbon monoxide to carbon dioxide, which is easily removed. In many electrolysis reactions hydrogen is an important by-product. Enormous quantities of hydrogen are used in the manufacture of ammonia and in the synthesis of methyl alcohol. It is an important combustible constituent of fuel. The hydrogenation of oils to produce edible fats, of coal to form synthetic petroleum, and of petroleum oils to enrich the gasoline fraction requires large amounts of hydrogen.The lightest in weight of all gases, hydrogen has been used for the inflation of balloons and dirigibles. It ignites very easily, however, a small spark causing it to burn, and several dirigibles have been destroyed by hydrogen fires. Helium, which has 92 percent of the lifting power of hydrogen and is not inflammable, is used whenever possible. Hydrogen is usually stored in steel cylinders at pressures of 120 to 150 atmospheres. Hydrogen is also used in high-temperature torches for cutting, melting, and welding metals.

All About Wireless Electricity

All About Wireless Electricity Wireless electricity is quite literally the transmission of electrical energy without wires. People often compare the wireless transmission of electrical energy as being similar to the wireless transmission of information, for example, radio, cell phones, or wi-fi internet. The major difference is that with radio or microwave transmissions, the technology focuses on recovering just the information, and not all the energy that you originally transmitted. When working with the transport of energy you want to be as efficient as possible, near or at 100 percent. Wireless electricity is a relatively new area of technology but one that is rapidly being developed. You may already be using the technology without being aware of it, for example, a cordless electric toothbrush which recharges in a cradle or the new charger pads that you can use to charge your cell phone. However, both of those examples while technically wireless do not involve any significant amount of distance, the toothbrush sits in the charging cradle and the cell phone lies on the charging pad. Developing methods of efficiently and safely transmitting energy at a distance has been the challenge. How Wireless Electricity Works There are two important terms to explain how wireless electricity works in, for example, an electric toothbrush, it works by inductive coupling and electromagnetism. According to the Wireless Power Consortium, Wireless charging, also known as inductive charging, is based on a few simple principles. The technology requires two coils: a transmitter and a receiver. An alternating current is passed through the transmitter coil, generating a magnetic field. This, in turn, induces a voltage in the receiver coil; this can be used to power a mobile device or charge a battery. To explain further, whenever you direct an electrical current through a wire there is a natural phenomenon that occurs, that a circular magnetic field is created around the wire. And if you loop/coil that wire that wires magnetic field gets stronger. If you take a second coil of wire that does not have an electrical current passing through it, and place that coil within the magnetic field of the first coil, the electric current from the first coil will travel through the magnetic field and started running through the second coil, thats inductive coupling. In an electric toothbrush, the charger is connected to a wall outlet that sends an electric current to a coiled wire inside the charger creating a magnetic field. There is a second coil inside of the toothbrush, when you place the toothbrush inside of its cradle to be charged the electric current passes through the magnetic field and sends electricity to the coil inside the toothbrush, that coil is connected to a battery which gets charged. History Wireless power transmission as an alternative to transmission line power distribution (our current system of electric power distribution) was first proposed and demonstrated by Nikola Tesla. In 1899, Tesla demonstrated wireless power transmission by powering a field of fluorescent lamps located twenty-five miles from their power source without using wires. As impressive and forward thinking as Teslas work was, at that time is was actually cheaper to build copper transmission lines rather than build the type of power generators that Teslas experiments required. Tesla ran out of research funding and at that time a practical and cost efficient method of wireless power distribution could not be developed. WiTricity Corporation While Tesla was the first person to demonstrate the practical possibilities of wireless power in 1899, today, commercially there is little more than electric toothbrushes and charger mats available, and in both technologies, the toothbrush, phone, and other small devices need to be extremely close to their chargers. However, an MIT team of researchers led by Marin Soljacic invented in 2005 a method of wireless energy transmission for household use that is practical at much greater distances. WiTricity Corp. was founded in 2007 to commercialize the new technology for wireless electricity.