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Ionic and Covalent bonding. David A. Katz Pima Community College Tucson, AZ. Ionic Bonding. Between a metal with low ionization energy ( little energy required to remove an electron) and a non-metal with high electronegativity and electron affinity - PowerPoint PPT Presentation
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Ionic and Covalent bonding
David A. KatzPima Community College
Tucson, AZ
Ionic Bonding
Between a metal with low ionization energy( little energy required to remove an electron)
and a non-metal with high electronegativity and electron affinity
( wants to grab an electron towards it)
Formation of NaCl
Lewis Structures for Ionic Compounds
Ba•• O•
•••
••
••O••
••
••Ba2+ 2-
Mg••
Cl•••
••
••Cl•••
••••
••Cl••
••
••Mg2+ -
2
BaO
MgCl2
Held together by strong electrostatic forces• Opposite charges attract• High melting points and boiling points• Regular structures – giant ionic lattices• When melted or dissolved ionic compounds conduct electricity
Properties of Ionic Compounds
Dissolving in Water
conductivity
Covalent Bond
• Between two elements with high ionization energy ( do not give up electrons easily) and high electronegativity ( try to grab the electron to each of them)
• Here neither atom is willing to give up its electron
• Instead the nuclei share the electrons between them
Lewis Structures
• Lewis structures are representations of molecules showing all electrons, bonding and non-bonding
Example :Li2 O
Lewis structures
F2 C2H6
Multiple Covalent bonds
• More than one pair of electrons can be shared between the same atoms
O2 N2
Properties of Covalent Molecules
• Contain non-metals• Weak bonds• Valence electrons are shared between atoms• Polar molecules dissolve in polar solvents• Volatile• Low melting and boiling points• Insoluble in water• Non polar compounds do not conduct
electricity; polar compounds can conduct small amounts of electricity