Question : In 1887, the Royal Society, London gave the Davy Medal for the "discovery of the periodic law of chemical elements" to ____________.

Option 1: Alexandre-Émile Béguyer de Chancourtois

Option 2: Dmitri Mendeleev

Option 3: Lothar Meyer

Option 4: John Alexander Reina Newland

Question : In 1955, which synthetic element was provisionally named Mendelevium in honour of Dmitri Mendeleev, who created one of the first periodic tables?

Option 1: Element 90

Option 2: Element 101

Option 3: Element 103

Option 4: Element 106

Question : When did Dmitri Mendeleev invent the periodic table, ordering the symbols of the chemical elements according to their atomic weights?

Option 1: 1794

Option 2: 1869

Option 3: 1890

Option 4: 1779

Question : Ozone protects biosphere from:

Option 1: X -rays

Option 2: Gamma rays

Option 3: Ultraviolet rays

Option 4: Infrared rays

Question : What is the correct order of radiations in descending order of frequencies?

Option 1: Infrared > Microwaves > Radio waves > X-rays

Option 2: Radio waves > X-rays > Microwaves > Infrared

Option 3: X-rays > Infrared > Microwaves > Radio waves

Option 4: Infrared > Microwaves > X-rays > Radio waves