Question

What is the main difference between Mendeleev's and modern periodic law?

Answer 1

NANBA..

Modern periodic table maintains uniformity. In Mendeleev's periodic table noble gases were not placed (as they are not discovered at that time). In Modern periodic table noble gases in a seperate group named as group-18. In Mendeleev's periodic table transition elements included with other elements.

Answer 2

Answer:

• Mendeleev's periodic table

1. elements are arranged in increasing order of their atomic masses.
2. It is not divided into any blocks.
3. There are 8 groups.
4. Isotopes could not be placed properly.

• Modern periodic table

1. Elements are arranged in increasing order of their atomic numbers.
2. It is divided into four blocks, namely s-block,p-block,d-block and f-block.
3. There are 18 groups.
4. Isotopes occupy the same position as the element.

Hope you understood mate!!!