Chemical bonding PPT Chemistry Class 11

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Chapter 4 Chemical Bonding Introduction to Chemistry
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Chapter 4 Chemical Bonding Introduction to Chemistry Why do atoms form bonds? ¦ The most stable arrangement of electrons in an 
atom is to have either a filled valence shell or to 
have 8 valence electrons (octet rule). ¦ Atoms obtain this stable electron arrangement by 
sharing, gaining or losing electrons – which is what 
creates chemical bonds. Chemical Bonding
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Chapter 4 Chemical Bonding Introduction to Chemistry Why do atoms form bonds? ¦ The most stable arrangement of electrons in an 
atom is to have either a filled valence shell or to 
have 8 valence electrons (octet rule). ¦ Atoms obtain this stable electron arrangement by 
sharing, gaining or losing electrons – which is what 
creates chemical bonds. Chemical Bonding Types of Chemical Bonds There are three major types of chemical bonds: ? ionic bonding ?covalent bonding ?metallic bonding The type of bond formed depends on the ionization 
energy and electronegativity of the atoms involved Chemical Bonding
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Chapter 4 Chemical Bonding Introduction to Chemistry Why do atoms form bonds? ¦ The most stable arrangement of electrons in an 
atom is to have either a filled valence shell or to 
have 8 valence electrons (octet rule). ¦ Atoms obtain this stable electron arrangement by 
sharing, gaining or losing electrons – which is what 
creates chemical bonds. Chemical Bonding Types of Chemical Bonds There are three major types of chemical bonds: ? ionic bonding ?covalent bonding ?metallic bonding The type of bond formed depends on the ionization 
energy and electronegativity of the atoms involved Chemical Bonding Ionization energy (IE)  = energy required to 
remove one valence electron. ¦ metals have LOW ionization energies ¦ non-metals have HIGH ionization energies Electronegativity (EN) = measure of the 
tendency for an atom to “steal” an electron from 
another atom within a chemical bond. Follows the 
same trends as electron affinity: ¦ metals have LOW electronegativities ¦ non-metals have HIGH electronegativities Chemical Bonding
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Chapter 4 Chemical Bonding Introduction to Chemistry Why do atoms form bonds? ¦ The most stable arrangement of electrons in an 
atom is to have either a filled valence shell or to 
have 8 valence electrons (octet rule). ¦ Atoms obtain this stable electron arrangement by 
sharing, gaining or losing electrons – which is what 
creates chemical bonds. Chemical Bonding Types of Chemical Bonds There are three major types of chemical bonds: ? ionic bonding ?covalent bonding ?metallic bonding The type of bond formed depends on the ionization 
energy and electronegativity of the atoms involved Chemical Bonding Ionization energy (IE)  = energy required to 
remove one valence electron. ¦ metals have LOW ionization energies ¦ non-metals have HIGH ionization energies Electronegativity (EN) = measure of the 
tendency for an atom to “steal” an electron from 
another atom within a chemical bond. Follows the 
same trends as electron affinity: ¦ metals have LOW electronegativities ¦ non-metals have HIGH electronegativities Chemical Bonding The Electronegativities of Common Elements