Structure of At...

By knowing the number of protons in a neutral atom, one can determine :

Who proposed the planetary model of the atom?

A neutral atom has $$12$$ electrons and $$13$$ neutrons. Its mass number is:

Atomic number of element ___________ is $$19$$.

Plum Pudding Model of the Atom was given by:

How much energy would be required by an electron while moving from ground state to 3rd excited state in $$H{e^ + }$$  ion 

According to Bohr's model of hydrogen atom, relation between principal quantum number n and radius of stable orbit is 

What idea states that lower energy level orbitals will be filled with electrons before higher energy level orbitals?

A neutral atom of fluorine has a mass number of $$19$$ and an atomic number of $$9$$. How many neutrons does it have?

Number of electrons surroundings Kr in $$Kr{F_2}$$ is: