Structure of Atom

The atoms have a planetary type of structure according to the classical Bohr model.

All the protons and neutrons are bound together at the centre of an atom. Which is called nucleus. while all the electrons were moving around the nucleus.

In an atom the number of protons and the number of electrons are equal. The number of protons is called atomic number. Total number of protons and neutrons in the nucleus is called atomic weight.

Electrons revolving around the nucleus do not more in the same orbit(Shell). Each shell contains fixed number of electrons. A shell can contain maximum of 2n² electrons.

Electrons closer to the nucleus has high force of attraction and electrons farther from the nucleus has less force of attraction. Show the electrons in the outer shell has loosely bonded to the nucleus.

the amount of energy required to extract the valence electrons from outer shell is very less.

When an atom absorbs energy from external source, its energy levels increases and electron moves to the next orbit. If such external energy is observed by valence electron, it tries to move to next orbit but there is no next orbit so it is completely removed from the force of attraction of nucleus.