1. Miss Elaine Macalinao Chemistry

2.  Using p.161-193 of the Modern Chemistry book, complete (as much as you can) the Chemical Bonding Chart given to you  If you are done, hold on to it as we will go over it afterwards

3.  Chemical bond: a mutual electrical attraction between the nuclei and valence electrons of different atoms that binds the atom together  Why form chemical bonds?  Decrease potential energy  Increase stability  All atoms trying to achieve a stable octet

4.  When atoms bond, their valence electrons are moved around in ways that make the atoms more stable  The way their valence electrons move around determine the type of bond that happens  3 major types of chemical bonds: ▪ Ionic ▪ Covalent ▪ Metallic

5.  Ionic bond: chemical bonding that results from the electrical attraction between large numbers of cations and anions  Electrons are either gained or lost by an atom  In doing so, both atoms often achieve the electron configuration of the nearest noble gas  Occurs between metals losing electrons to nonmetals  Very strong bond

6.  Ionic compound: composed of positive and negative ions that are combined so that the numbers of positive and negative charges are equal  Most ionic compounds exist as crystalline solids ▪ 3D network of positive and negative ions mutually attracted to one another ▪ Ex: rocks, minerals  Ionic compounds are not composed of independent, neutral units that can be isolated and examined

7. IONIC DefinitionChemical bonding that results from the electrical attraction between large numbers of cations and anions Types of atoms involvedMetals & nonmetals Method of bond formationTransfer of electrons Type of structureCrystal lattice Physical stateSolid Melting pointHigh Solubility in waterYes Electrical conductivityYes Other properties-- Image

8.  Covalent bond: chemical bonding that results from the sharing of electron pairs between two atoms  Neither atom has an electrical charge  Forces between atoms are weak  Bonding between atoms of the same elements is completely covalent

9.  Molecule: a neutral group of atoms that are held together by covalent bonds  Molecular compound: a chemical compound whose simplest units are molecules  Diatomic molecule: a molecule containing only two atoms

10. COVALENT DefinitionChemical bonding that results from the sharing of electron pairs between atoms Types of atoms involvedNonmetals Method of bond formationSharing of electrons Type of structureMolecules Physical stateLiquid or gas Melting pointLow Solubility in waterUsually not Electrical conductivityNo Other propertiesOdorous Image

11.  Metallic bonding: the chemical bonding that results from the attraction between metal atoms and the surrounding sea of electrons  Within metals, vacant orbitals allow the atoms’ outer energy levels to overlap  Result = electrons become delocalized ▪ Delocalized: not belonging to any one atom, but freely move about the metal’s network of empty atomic orbitals

12.  Metallic Properties  Freedom of electrons to move in a network of metal atoms account for the high electrical and thermal conductivity characteristic of metals  Metals can absorb a wide range of frequencies due to the many orbitals separated by extremely small energy differences they contain ▪ Absorption of light results in the excitation of metal atoms’ electrons to higher energy levels ▪ De-excitation responsible for the shiny appearance of metal surfaces

13.  Two important properties related to characteristics of metals:  Malleability: the ability of a substance to be hammered or beaten into thin sheets  Ductility: ability of a substance to be drawn, pulled, or extruded through a small opening to produce a wire  Characteristics possible because metallic bonding is the same in all directions throughout the solid ▪ One plane of atoms in a metal can slide past another without encountering any resistance or breaking any bonds

14. METALLIC DefinitionChemical bonding that results from the attraction between metal atoms and the surrounding sea of electrons Types of atoms involvedMetals Method of bond formationElectrons are delocalized among metal atoms Type of structure“Sea of electrons” Physical stateSolid Melting pointVery high Solubility in waterYes Electrical conductivityYes Other propertiesMalleable, ductile, lustrous Image

15.  Most bonds are a blend of ionic and covalent characteristics  Difference in electronegativity determines the bond type  A large difference in electronegativity in a bond will result in ionic bonding  A small difference between two atoms will results in covalent bonding

16.  Non-polar covalent bond: a covalent bond in which the bonding electrons are shared equally by the bonded atoms, resulting in a balanced distribution of electrical charge  Polar-covalent bond: a covalent bond in which the bonded atoms have an unequal attraction for shared electrons

17. Electronegativity Difference Bonding typeHow it looks like 0.0 – 0.3 Non-polar covalent 0.4 – 1.9 Polar covalent 2.0 – 3.3 Ionic

18.  Chemical Bonding Video Chemical Bonding Video

19. Essay – write a 5-paragraph essay comparing and contrasting each bonding type. The essay should incorporate the major properties from the Bonding Chart.