Question

Give an account of history of the development of periodic table.

Answer 1

henry Moseley with the help of other scientists decided to arrange the elements in order.

they updated mendeeleev's periodic table by rearranging some elements and adding new elements etc.

they played a key role in development of periodic table

Answer 2

Hey Vaibhav,

◆ History of periodic table -

1) Dobereiner's triads -

- Dobereiner paired elements in group of three such that atomic mass of middle element was the average of 1st & 3rd element.

2) Newland's octaves -

- Newlands observed that when elements are arranged in increasing order of their atomic mass, every 8th element possess similar properties wrt 1st element.

3) Mendeleev's periodic table -

- Mendeleev also arranged elements in increasing order of their atomic masses, but also kept in mind that similar elements are in same group.

4) Modern periodic table -

- Henry Moseley arranged elements in increasing order of their atomic numbers instead of atomic masses.

Thanks for asking..