State any three demerits of Mendeleev’s periodic table.
Advertisement Remove all ads
Solution
Demerits of Mendeleev’s periodic table:
- Hydrogen resembles alkali metals and halogens. So, a correct position could not be assigned to hydrogen in the periodic table.
- The position of isotopes could not be explained. Isotopes are atoms of the same element with similar chemical properties but different atomic masses. If the elements are arranged according to atomic masses, the isotopes should be placed in different groups of the periodic table.
- At certain places, an element of higher atomic mass has been placed before an element of lower atomic mass. Example: Cobalt (Co = 58.93) is placed before nickel (Ni = 58.71).
Concept: Mendeleev’s Periodic Table
Is there an error in this question or solution?
Advertisement Remove all ads
APPEARS IN
Advertisement Remove all ads
Advertisement Remove all ads