An alkaline earth metal 

The number of electrons present in the valency shell of a halogen is:

Element 'A' has electronic configuration 2, 7; 'B' has electronic configuration 2, 8, 5 and 'C' has electronic configuration 2, 8, 7. Which two elements will exhibit similar chemical properties?

The element with atomic number 26 will be found in group

The inert gas which lies in third period is 

Which of the element whose atomic number is given below cannot accommodate in the present set up of the long form of the periodic table?

The amount of energy released when one or more electrons is added to the neutral atom is 

Which of the following sets of atomic number belong to that of alkali metals?

The ionization potential across a period

In the periodic table alkali metals are placed in the group ..........