Question

4 similarities for Mendeleev's periodic table and modern periodic table.

Answer 1

1.anomalous position of hydrogen.
2.separate column for noble gases.
3. both are organised by groups and family.
4.both are organised by noticing similar chemical and physical properties.

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!!!