Question

write down five major differences between mendeleev's periodic table and modern periodic table​

Answer 1

Answer:

S. No. Mendeleev's Period Table / Modern Periodic Table (i) Elements have been arranged in increasing order of atomic masses.

Element have been arranged in increasing order of their atomic number.

(ii) It consists of 8 groups.

It consists of 18 groups.

(iii) All the groups from I to VIII are divided into two sub-groups

No sub-groups.

(iv) He left some gaps in the table for undiscovered elements .

All elements are filled in increasing order of atomic number. No gaps Ieft in the periodic table.

(v) Isotopes were placed in different groups.

Isotopes were placed ln same group.