Question

Who developed a long form of the periodic table?

A. Lothar Meyer

B. Neil Bohr

C. Mendeleev

D. Mosely

Answer 1

Hint: In the periodic table the elements are arranged in horizontal and vertical rows according to their physical and chemical properties. So many scientists tried to arrange the chemical elements as a result several periodic tables came into light.

Complete answer:

- In the question it is asked to find the person among the given options related to the discovery of the long form of the periodic table.

- Coming to the given options, option A, Lothar Meyer.

- Lothar Meyer is the scientist who discovered or developed the periodic table which contains 28 elements only.

- Lothe Meyer developed the periodic table with 28 elements based on their valence.

- Therefore option A is wrong.

- Coming to option B, Neil Bohr. He postulated a theory for the hydrogen atom as well as using the Mosley’s principle Bohr discovered the long form of periodic table.

- Therefore option B is incorrect.

- Coming to option C, Mandeleev. He arranged the elements in the periodic table according to atomic mass but was unable to arrange all the elements in the periodic table.

- Therefore option C is incorrect.

- Coming to option D, Mosley. He developed the periodic table . According to Moseley, similar properties recur periodically when elements are arranged according to increasing atomic number. 

Therefore Bohr is the scientist who discovered the long form of the periodic table. So, the correct option is (B).

Note:
Since the 1950s chemicals have been produced from coal. Coal gasification to produce syngas is the main route of these products. Coal can be used as a feedstock in the production of a wide range of chemical fertilizers and other chemical products.