During the formation of a chemical bond, atoms combine together by gaining,losing or sharing electrons in such a way that they acquire stable noble gas configuration.

The atom which gains electrons is called ________ atom.

_______ is the first Noble gas.

How many Oxygen atoms are present in Phosphoric acid?

_________possess practically no tendency to from chemical bonds and to enter into chemical combination.

The theory of chemical bonding reveals that the formation of a chemical bond involves a decrease in the _________ of the system.

 What is the second ionization enthalpy(kJ mol^-1) of Mg?

________ introduced electron dot symbols to denote the valence electrons in an atom.

 For which element the second ionization enthalpy(kJ mol^-1) is 979?

For which element the second ionization enthalpy(kJ mol^-1) is 965?