the neutron was discovered in 1932 then how mendeleev calculated atomic mass

Asked by devchaudhari | 18th Feb, 2019, 04:14: PM

Expert Answer:

Mendeleev was an important contributor to the early development of the Periodic table.

He believed that the atomic mass of an element was the most fundamental property in classifying the elements.

So, Mendeleev arranged elements in the increasing order of their atomic weights which we are now known as relative atomic mass.

Yes, it is right that when Mendeleev formed the periodic table at that time when neutrons were not discovered.

So he used the relative atomic mass which is defined as:

The relative atomic weight of an element is the number of times one atom of the element is heavier than 1/12 times of the mass of an atom of carbon-12.

Using the above method in 1862, Alexandre Beguyer de Chancoutois made a list of known elements in the order of increasing weight and this was about 3 years before Newlands and 7 years before Mendeleev's periodic system was developed.

Mendeleev used this list of elements in his discovery.

Answered by Ramandeep | 18th Feb, 2019, 06:14: PM