Question

Argon was discovered by:
(A) Rayleigh
(B) Frankland and Lockyer
(C) Jansen
(D) Ramsay

Answer 1

Hint:Argon is inert or noble gas, that means which does not react with any substances in any chemical reaction. Due to its inert nature, Argon could not be discovered very easily. But in 1894, with the help of Spectroscopy, it was seen that there is presence of inert nature gas called Argon.

Complete step by step answer:
The element Argon with atomic number 18, is a noble gas. The position in the periodic table is in 18th group, and 3rd period. Due to the inert nature of gas, it was not discovered earlier.
Henry Cavendish, an English Chemist while separating oxygen and nitrogen from air, came to know that
some part of the air remained. He could not identify the gas, but could predict that there is some small part
of gas remaining back. This he could identify 200 years before the actual discovery.
When William Ramsay did same experiment of Cavendish, he also observed that some small amount of
gas remained after extraction of oxygen and nitrogen. But he had an advantage that spectroscopy was
present at his times. Spectroscopy is process in which light is produced by heating element, and every
element produces different coloured lines. Thus, a new element could be identified by this. He named this as Argon.
Thus, in process of fractional distillation experiment performed by English Chemists William Ramsay and
John William Strutt, or popularly known as Lord Rayleigh, in 1894 discovered this inert or noble gas. This
was among the first noble gas to be discovered.
Thus the correct options are (A) Rayleigh and (D) Ramsay.

Note:
Do not get confused between Argon and helium, as Argon was first inert gas discovered while
Helium was the first inert gas discovered on the sun. We should know that, Lord Rayleigh and William Ramsay both did experiments and got same results at same time, then both of them decided to make
announcement of their work together. Thus both of them discovered Argon together.