Question

Mendeleef’s Periodic Table is upset by the fact that

Solution

Correct option is

Many elements has several isotopes

Mendeleef failed to assign positions to isotopes on the basis of atomic mass according to his periodic law.

SIMILAR QUESTIONS

Q1

Which of the following pairs has both members of the same period of the Periodic Table? 

Q2

An element with atomic number 20 will be placed in which period of the Periodic Table? 

Q3

The elements with atomic numbers 9, 17, 35, 53, 85 are all

Q4

In which block does 106th element belong?

Q5

Which group of the Periodic Table does not contain only metals?

Q6

The elements having the electronic configuration

[kr] 4d10f14, 5s2p6d2, 6s2 belongs to which block

Q7

Which pair of atomic numbers represents s-block elements?

Q8

If Aufbau rule is not followed, K-19 will be placed in

Q9

Which of the following has largest size?

Q10

Which of the following has largest ionic radius?