Neon is an inert gas and hence is classified as simple asphyxiant a substance which can cause unconsciousness or death by suffocation but has no other health effects, hence upon excessive inhalation can cause vomiting, nausea, dizziness or suffocation leading to unconsciousness or death. Liquefied neon is used as a cryogenic refrigerant on commercial scale.Neon is used in high voltage indicators, vacuum tubes, lightning arresters, television tubes, wave-meter tubes and helium-neon lasers.It is used in sign boards because of its bright reddish orange light.Neon is highly volatile and forms no compounds to fix it to solids. Its triple point, the point at which the three phases of a substance coexist in thermodynamic equilibrium, is 24.5561 K (248.5 degree Celsius). It is identified as most electronegative element based on Allen electronegativity scale. The bulk modulus of neon is 654 GPa while melting point is -248.6 degree Celsius and it has boiling point of -246 degree centigrade. Neon is a colourless, odourless monoatomic gas. It is the second lightest noble gas and glows reddish-orange in vacuum discharge tube. It is the first element forming a true octet of electrons and hence is inert just like its lighter analogue, helium. Neon is a noble gas belonging to first p-block of periodic table. Neon is relatively expensive as it is rare and can only be obtained from air. Industrially it is produced by cryogenic fractional distillation of liquefied air. All these properties diminishes its probability of being trapped in condensing dust and gas clouds which forms the warmer yet smaller solid planets like Earth. Neon is the fifth most abundant element in the universe with respect to mass although it is relatively less on earth due to its high vapour pressure at low temperature, its lightness and its chemical inertness. In our Earth’s atmosphere neon comprises of 1 part in 55,000 (18.2 ppm) by volume or 1 part in 79,000 of air by mass. Neon is produced by the fusion of helium and oxygen in the alpha process. Such high temperatures are available at the cores of stars of more than three solar masses. Neon is produced in stars as its production requires temperatures above 100 megakelvins. Neon Periodic Table ClassificationĬolorless gas exhibiting an orange-red glow when placed in an electric field J.J Thomson used neon gas for experimentation and concluded some of the atoms in neon gas have higher mass than the rest. Neon gas played an important role in the discovery of isotopes of stable atoms. After 1902, industrial quantities were produced by air-liquefaction businesses which were used in advertising signs. It was named neon because of its Greek analogue meaning new. Neon stood out because of its brilliant red light under spectroscopic discharge. Ramsay discovered it by chilling an air sample until it became a liquid then capturing the gases released from the liquid as it was warmed. Neon was discovered in 1898, in London, by British chemists Morris W. It has a brilliant red light and is widely used in advertising signs. Travers and Sir William Ramsay in London. ![]() At present, values expressed in u, AMU, amu, and Da all describe the exact same measure.Neon is a noble gas discovered in 1898 by British chemists Morris W. Many scientists kept using the amu, just recognizing it was now based on carbon rather than oxygen. However, u and Da were not universally adopted. The new unit was given the symbol u to replace amu, plus some scientists called the new unit a Dalton. So, in 1961 the decision was made to use carbon-12 as the basis for the unit (to avoid any confusion with an oxygen-defined unit). ![]() ![]() Some scientists used an AMU based on the natural abundance of oxygen, while others used an AMU based on the oxygen-16 isotope. When the existence of isotopes was discovered in 1912 and isotopic oxygen in 1929, the definition based on oxygen became confusing. Wilhelm Ostwald suggested that relative atomic mass would be better if expressed in terms of 1/16th the mass of oxygen. He proposed the use of hydrogen-1 (protium). John Dalton first suggested a means of expressing relative atomic mass in 1803.
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