Structural Behaviors — 

Helium was first discovered as a yellow line in the sun’s spectrum in 1868 by Pierre-Jules-César Janssen, a French astronomer, while studying a solar eclipse. However, it was Sir Norman Lockyer, an English astronomer, who discovered that having a wavelength of 587.49 nanometers, the yellow line could not have been produced by any known element at the time. Lockyer named the newly discovered element Helium. Helium is in group 18 on the periodic table, which contains the noble gases, is represented by the letters: He, and its atomic number is 2. Helium is the second lightest gas, weighing 4.002602 AMU. Helium s a colorless, odorless, insipid, and non-toxic gas. Helium has a melting point of -272.2 (26 ATM) °C and a boiling point of -268.9 °C.

Chemical Behaviors — 

Helium is a colorless, odorless, tasteless gas. No compounds of helium exist. Helium is the second most abundant element in the universe, as well as the second simplest of the chemical elements. At very low temperatures At a temperature of about -271°C (-456°F) helium can become a superfluid — It can flow upwards out of a container, against the force of gravity. It can also squeeze through very small holes that should be able to keep it out. Helium is the only gas that cannot be made into a solid simply by lowering the temperature. It is also necessary to increase the pressure on the gas in order to make it a solid. The forms of helium are so different that they are given different names. Above -271°C, liquid helium is called helium I; below that temperature, it is called helium II.

Importance of Helium on Earth — 

There are many uses of helium of course probably most popularly, to fill balloons (lifting) but it is also used for fiber optics, cutting and welding, pressurizing and purging, medical imaging, diving, and electronics.Helium can be used to help patients with lung ventilation, pulmonary function testing, some laparoscopic surgeries, etc.. Helium helps divers go deeper under water by replacing nitrogen in diving gas mixtures, it’s used in many scientific practices for its cooling property, it also fills airbags in vehicles in case of collision. 

Reference URLs — 

https://www.lenntech.com/periodic/elements/he.htm

https://education.jlab.org/itselemental/ele002.html

http://www.chemistryexplained.com/elements/C-K/Helium.html

https://sciencing.com/everyday-uses-helium-gas-8041697.html

http://www.airproducts.com/~/media/Files/PDF/microsites/doe-canyon/doe-canyon-why-is-helium-important.pdf