Question

Helium was discovered by:
A.Crooks
B.Rutherford
C.Frankland and Lockyer
D.Dorn

Answer 1

Hint: Helium is the Nobel gas and it has the atomic number of 2 and the electronic configuration is also 2 thus it has 2 electrons in its outermost shell and the only shell it has and is stable and unreactive in nature due to the completely filled atomic orbital.

Complete answer:
Helium was discovered by Frankland and Lockyer in 1868. The symbol of the gas Helium is He. It is found in the atmosphere like the other Noble gases except the Noble gas Radon. The gas is odourless, tasteless and non-toxic in nature and is the first gas in the group of the Noble gases in the Periodic Table. Helium and neon are found from radioactive origins.
 Among all the elements its boiling point is the lowest and is the second most abundant element in the universe after the lightest element hydrogen. It is present at about 24% of the total elemental mass, which is more than 12 times the mass of all the heavier elements combined. Its abundance is very high in the sun and in Jupiter as well and the main cause of it is the high nuclear binding energy compared to the other elements of the group. Thus due to this reason only it is the main product of nuclear fission and radioactive decay as well. The majority of the helium gas was formed during the Big Bang. By the nuclear fusion of the stars a large amount of helium is created in the atmosphere.

Thus option C. Frankland and Lockyer is the correct option

Note:
Helium gas is used in the scientific balloons and to inflate blimps. It is used as an inert shell for the welding purpose. It is also used as a fuel and in the rockets as well along with the supersonic wind tunnels mainly all because of the inert nature of the gas.