CHAPTER 1
.THE'LECT}ONIC STRæ'TtJRES OF ATOMSi
PERIODIC TABLE AND C'"EMICAL BONDS
1•.1- Arrangement Of Fundak'tal Particles of Matter Fundamental Particles
All matter is mådé of atoms'. turn, atoms consist of three main fundamental partiCIes. They are protons, neutrons and electrons. The masses and charges of these particles are shown in Table. 1.1
Arrangement of the Fundamental Particles in the Atom
helium atom}.
( P = proton n = neutron )
The atom may be pictured-as follows.
The atom has a Small, dense, positively charged centre called the nucleus. This nucleus contains protons and neutrons. Outside and around the nucleus,
electr6ns move in circular dr near circular orbits. The negative charge of the electröns balances the positive charge of the nucleus. The atom as a whole is neutral. Most of
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