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Physical science. notes. Valence electrons. Electrons on outer shell. Valence electrons. Group 1- 1 valence electron Group 2- 2 valence electrons Group 3- 3 valence electrons Group 4- 4 valence electrons Group 5- 5 valence electrons Group 6- 6 valence electrons
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Physical science notes
Valence electrons • Electrons on outer shell
Valence electrons • Group 1- 1 valence electron • Group 2- 2 valence electrons • Group 3- 3 valence electrons • Group 4- 4 valence electrons • Group 5- 5 valence electrons • Group 6- 6 valence electrons • Group 7- 7 valence electrons • Group 8- 8 valence electrons-except He (2)
Types of bonding • Ionic bond • Covalent bond • Metallic bond
Ionic bonds • An ionic bond is formed between a metal and a non-metal. Non-metals(-ve ion) are "stronger" than the metal(+ve ion) and can get electrons very easily from the metal. • These two opposite ions attract each other and form the ionic bond.
Common ionic bonds • NaCl • KBr • LiO
Covalent bonds • A covalent bond is formed between two non-metals that have similar electronegativities. Neither atom is "strong" enough to attract electrons from the other • For stabilization, they share their electrons from outer molecular orbit with others
Metallic bonding • Formed between atoms of metallic elements • Electron cloud around atoms • Good conductors at all states, lustrous, very high melting points • Examples; Na, Fe, Al, Au, Co
practice • What type of bond?
NaCl • CH4
answers • NaCl=ionic (metal+nonmetal) • CH4=covalent (2 nonmetals share e-) • Silver (Ag) below=metallic bond