TYPES OF CHEMICAL BONDS IONIC BONDS COVALENT BONDS HYDROGEN BONDS METALLIC BONDS.

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  • TYPES OF CHEMICAL BONDSIONIC BONDSCOVALENT BONDSHYDROGEN BONDSMETALLIC BONDS

  • IONIC BONDINGWhen an atom of a nonmetaltakes one or more electronsfrom an atom of a metalso both atoms end up witheight valence electrons

  • IONIC BONDINGIS THE COMPOUND AN IONIC COMPOUND?

  • IONIC BOND FORMATIONNeutral atoms come near each other. Electron(s) are transferred from the Metal atom to the Non-metal atom. They stick together because of electrostatic forces, like magnets.

  • IONIC BONDINGMetals will tend to lose electrons and becomePOSITIVE CATIONS

  • IONIC BONDINGNonmetals will tend to gain electrons and becomeNEGATIVE ANIONS

  • Properties of Ionic CompoundsCrystalline structure.A regular repeating arrangement of ions in the solid.Ions are strongly bonded.Structure is rigid.High melting points- because of strong forces between ions.

  • Crystalline structureThe POSITIVE CATIONS stick to the NEGATIVE ANIONS, like a magnet.

  • Do they Conduct?Conducting electricity is allowing charges to move.In a solid, the ions are locked in place.Ionic solids are insulators.When melted, the ions can move around.Melted ionic compounds conduct.Melting points always above 800C.Dissolved in water they conduct.

  • Ionic solids are brittle

  • Ionic solids are brittleStrong Repulsion breaks crystal apart.

  • COVALENT BOND FORMATIONWhen one nonmetal shares one or more electrons with an atom of another nonmetal so both atoms end up with eight valence electrons

  • COVALENT BONDINGIS THE COMPOUND A COVALENT COMPOUND?YES since it is made of only nonmetal elements

  • Covalent bondingFluorine has seven valence electrons

  • Covalent bondingFluorine has seven valence electronsA second atom also has seven

  • Covalent bondingFluorine has seven valence electronsA second atom also has sevenBy sharing electrons

  • Covalent bondingFluorine has seven valence electronsA second atom also has sevenBy sharing electrons

  • Covalent bondingFluorine has seven valence electronsA second atom also has sevenBy sharing electrons

  • Covalent bondingFluorine has seven valence electronsA second atom also has sevenBy sharing electrons

  • Covalent bondingFluorine has seven valence electronsA second atom also has sevenBy sharing electrons

  • Covalent bondingFluorine has seven valence electronsA second atom also has sevenBy sharing electronsBoth end with full orbitals

  • Covalent bondingFluorine has seven valence electronsA second atom also has sevenBy sharing electronsBoth end with full orbitalsFF8 Valence electrons

  • Covalent bondingFluorine has seven valence electronsA second atom also has sevenBy sharing electronsBoth end with full orbitalsFF8 Valence electrons

  • Single Covalent BondA sharing of two valence electrons.Only nonmetals and Hydrogen.Different from an ionic bond because they actually form molecules.Two specific atoms are joined.In an ionic solid you cant tell where the electrons came from

  • WaterEach hydrogen has 1 valence electronEach hydrogen wants 1 moreThe oxygen has 6 valence electronsThe oxygen wants 2 moreThey share to make each other happy

  • WaterPut the pieces togetherThe first hydrogen is happyThe oxygen still wants one moreH

  • WaterThe second hydrogen attachesEvery atom has full energy levelsHH

  • Two types of covalent bonds:Sigma bonds: represented by the symbol two orbitals with a DIRECT overlay (so it falls DIRECTLY between the nuclei of the atoms in the bond)

  • Two types of bondsAnother view of sigma bonds (showing electron clouds):

  • Two types of covalent bonds:Pi bonds, represented by the symbol two lobes of one involved atomic orbital overlap two lobes of the other involved atomic orbital.

  • Two types of covalent bondsSo single bonds (or the FIRST bond formed) is a bond, and the second and/or third are always bonds

  • Coordinate Covalent BondWhen one atom donates both electrons in a covalent bond.Carbon monoxideCO

  • Coordinate Covalent BondWhen one atom donates both electrons in a covalent bond.Carbon monoxideCOOC

  • Coordinate Covalent BondWhen one atom donates both electrons in a covalent bond.Carbon monoxideCOOC

  • Coordinate covalent bondOther examples:

  • Polar MoleculesMolecules with a positive and a negative endRequires two things to be true The molecule must contain polar bonds This can be determined from differences in electronegativity.Symmetry can not cancel out the effects of the polar bonds.Must determine geometry first.

  • Is it polar?HFH2ONH3 CCl4 CO2

  • Intermolecular ForcesWhat holds molecules to each other

  • Intermolecular ForcesThey are what make solid and liquid molecular compounds possible.The weakest are called van der Waals forces - there are two kindsDispersion forces Dipole Interactionsdepend on the number of electrons more electrons stronger forcesBigger molecules

  • Dispersion forcesWhen electrons temporarily clump in one part of a moleculeResults in a temporary attractive force from a temporary dipole

  • Dispersion ForcesAlso called London Forces or Van der Waals forcesThe larger the molecule, the greater the additive effect

  • Dispersion ForcesThis is why gasoline is a solid at room temperature, but methane is a gas

  • Dipole interactionsDepend on the number of electrons More electrons stronger forcesBigger molecules more electronsFluorine is a gasBromine is a liquidIodine is a solid

  • Dipole interactionsOccur when polar molecules are attracted to each other.Slightly stronger than dispersion forces.Opposites attract but not completely hooked like in ionic solids.

  • Dipole Interactionsd+ d-

  • Hydrogen bondingAre the attractive force caused by hydrogen bonded to F, O, or N.F, O, and N are very electronegative so it is a very strong dipole.The hydrogen partially share with the lone pair in the molecule next to it.The strongest of the intermolecular forces.

  • Hydrogen Bonding

  • Hydrogen bonding

  • Metallic BondsMetals hold onto their valence electrons very weakly.Think of them as positive ions floating in a sea of electrons.

  • Sea of ElectronsValence electrons are free to move through the solid.Metals conduct electricity.

  • Metals are MalleableHammered into shape (bend).Ductile - drawn into wires.

  • Malleable

  • MalleableElectrons allow atoms to slide by.

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