Which atom has the lowest ionization energy? Which atom has biggest atomic redius?

What is the ionisation energy of hydrogen atom?

What is inter - atomic force ?

State modern periodic law. What do you understand by first ionization potential? "The first ionization energy of nitrogen atom is greater than that of oxygen atom" Explain

An atom has electronic configuration 2,8,7. What is the atomic number of this element?

Define the atomic mass unit.

Define Atomic size.

Draw the different energy level diagram for a hygrogen atom.