Noble Gas and Helium
Although Helium exists in the atmosphere of Earth in small quantities, it is one of the most common element in the universe. It is a rare gas on earth. Helium was first discovered by Pierre Janssen in the spectrum of the sun during an eclipse in 1868. It was shortly identified as an element and was named by the chemist Sir Edward Frankland and the British astronomer Sir Joseph Norman Lockyer. Helium has an atomic number of 2 and an atomic weight of 4.002602. Helium is represented by the symbol of He. Helium is the second lightest element after Hydrogen and considered as the least reactive element. The more an element is reactive, the more flammable it is. It is considered a non-metal element with a number of 2 stable isotopes. It is a gas at room temperature with a density of 0.0001785 per cubic centimeter. Helium is an odorless, colorless, tasteless and nontoxic element. Natural gas is the major source of helium. The natural decay of alpha-emitting radioactive minerals in the Earth's crust creates helium and migrates to areas where gas is trapped. It is extracted from the gas by turning the gas stream into a liquid and by removing all other components. Helium is more abundant in space such as stars and nebulae because it enters the atmosphere and escapes into space due to its low molecular weight. Helium is one of the favorite and most known element world wide. This paper will inform you how Helium was discovered, how it is used today, how it is extracted and the different helium states. Helium doesn’t react with any elements, including itself. It is so tiny that it is used to find microscopic leaks. How did we discover such a small and admirable element? In 1868, Pierre Janssen and Norman Lockyer were observing the spectral lines of the sun during a solar eclipse and they both found an unexpected yellow spectral line. Lockyer though that this line was caused by an element undiscovered on Earth up until now. It was naturally assumed that it was an element of
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