According to Mendeleev's Periodic Law, the elements were arranged in the periodic table in the order of

The law of triads is applicable to

Why did Newland's law of Octaves fail?

In Mendeleev's periodic table, gaps were left for the elements to be discovered later. Which of the following elements found a place in the periodic table later

Which of the following elements was present in Mendeleev's periodic table?

Which of the following statements about the Modern Periodic Table are incorrect? Choose the correct option

i)  The elements in the Modern Periodic Table are arranged based on their decreasing atomic number

ii)  The elements in the Modern Periodic Table are arranged based on their increasing atomic masses

iii) Isotopes are placed in adjoining groups in the periodic table.

iv) The elements in the Modern Periodic Table are arranged based on their increasing atomic number 

The modern periodic table has ........... vertical columns called groups and horizonal rows called periods.

Which of the following elements exhibit a maximum number of valence electrons?

The elements with atomic numbers 57 to 71 are called

The atomic radius ........... across the period from left to right whereas the atomic radius as one moves from top to bottom.

Which among the following elements has the largest atomic radii?

Which one of the following does not increase while moving down the group of the periodic table?

On moving left to right in a period, in the periodic table, the size of the atom:

The ionization potential ............... across the period from left to right whereas it as one moves form top to bottom.

If the difference in electro-negativities of the combining atoms is zero, then the bond formed is a 

Which of the following set of elements is written in order of their increasing metallic character?

Which of the following alkali metals is a radioactive element?

Halogens have ............ electrons in their last shell.

Which of the following statements about halogens is incorrect?

Alkali metals has ............. number of valence electrons.