In Mendeleev's periodic table some pair of elements do not follow increasing order of atomic weight known as anomalous pair. The correct example of anomalous pair is

Which of the following pair of element has incorrect order of atomic radii ?

In Mendeleev's periodic table gap was not left for one of the following elements. This element is:

Mendeleev's periodic table helped in correct determination of atomic masses of elements

The following are some statements about Mendeleeff's periodic table i) It is based on increasing order of atomic numbers ii) Mendeleeff corrected the atomic weight of some elements like Be, In etc iii) (Ar,K), (Co,Ni), (Te,I) are three inverted pairs

The following are some statements about Mendeleev's peridioc table (i) It is based on increasing order of atomic numbers . (ii) Mendeleev corrected the atomic weight of some elements like Be, In, U, etc. (iii) (Ar, Ca), (Co, Cu), (Te , F) are three inverted pairs. (iv) it is based on increasing order of atomic weights.