Structure of Atom

Structure of Atom

• An atom consists of one central nucleus. The nucleus is made up of positive protons and charge less neutrons.

• This nucleus is surrounded by numbers of orbital electrons. Each electron has a negative charge of - 1.602 × 10 ^{- 19} Coulomb and each proton in the nucleus has a positive charge of + 1.602 × 10 ^- 19 Coulomb.

• Because of the opposite charge there is some attraction force between the nucleus and orbiting electrons.

• Electrons have relatively negligible mass compared to the mass of the nucleus.

• The mass of each proton and neutrons is 1840 times the mass of an electron. As the modulus value of each electron and each proton are same, the number of electrons is equal to the number protons in an electrically neutral atom.

• An atom becomes positively charged ion when it loses electrons and similarly an atom becomes negative ion when it gains electrons.

• These electrons require a very small amount of energy to detach themselves from their parent atoms.

• These electrons are referred as free electrons which move randomly inside the substance and transferred from one atom to another.

• Any piece of substances which as a whole contains an unequal number of electrons and protons is referred as electrically charged.

• When there is more number of electrons compared to its protons, the substance is said to be negatively charged and when there is more number of protons compared to electrons, the substance is said to be positively charged.