Question

State the difference between mendeleev periodic table and modern periodic table

Answer 1

1.Mendeleev's periodic table is based on atomic massModern periodic table is based on atomic number
2.Mendaleev's periodic table contains about 66 elements.Modern periodic table contains about 112 elements
3.In Mendeleev's  periodic table there were gaps for undiscovered elements.Modern periodic table maintains uniformity.
4.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.

5.In Mendeleev's periodic table transition elements included with other elementsIn
Modern periodic table transition elements  placed in separate block.

Answer 2

Answer:

Difference between Mendeleev's periodic table and modern periodic table.

Explanation:

Mendeleev's periodic table

1. Elements are arranged based on atomic mass.

2. Position of elements is based on properties.

3. There are 8 groups Mendeleev's periodic table.

4. Elements with different properties are in same group.

5. Isotopes can't be classified in this table.

Modern periodic table:

1. Elements are arranged based on atomic number.

2. Position of elements is based on electronic configuration.

3. There are 18 groups in modern periodic table.

4. Elements in same group show same properties.

5. Isotopes having same atomic number can be classified in this table.