• Helium is a element that symbolizes as H and has an atomic mass of 2 , 2 electrons ,2 protons and 0 neutrons.

• Its atomic weight is 4 making it the second lightest element in the world

• This is how an helium atom looks like , it has 2 protons , 2 neutron and 2 electrons

• Helium is considered as the second element created after the big bang in the periodic table

• Helium can be in 3 states of matter

Solid form of helium

• Helium can stay in solid , Solid helium can be obtained only under high-pressure conditions

• Willem Hendrik Keesom was eventually able to solidify 1 cm3 of helium in 1926 by applying additional external pressure.

Liquid form of helium

• At standard pressure, the chemical element helium exists in a liquid form only at the extremely low temperature of −269 °C (−452.20 °F; 4.15 K).

• Its boiling point and critical point depend on which isotope of helium is present: the common isotope helium-4 or the rare isotope helium-3.