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When Mendeleev developed his periodic ta...

When Mendeleev developed his periodic table, chemists knew nothing about the internal structure of atom. His classification was based on their atomic wetghts. Several anomalies persisted in the table with regard to the correct order of atomic weights of
(i) `K`adn`Ar` (ii) `Co`and`Ni`
(iii) `Te`and`I`

A

`(i),(ii)`

B

`(i),(ii),(iii)`

C

`(ii),(iii)`

D

`(i),(iii)`

Text Solution

Verified by Experts

The correct Answer is:
B
Atomic mass of `Ar(39.95u)` is greater than thet of `k(39.10u)` but `K` is placed after `Ar`. Similarly for others.
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R SHARMA-CLASSIFICATION OF ELEMENTS AND PERIODICITY IN ELEMENTS-Follow-up Test 6
  1. When Mendeleev developed his periodic table, chemists knew nothing abo...

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