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Homework 2 6 Modern Chemistry Chapter

Presentation on theme: "Modern Chemistry Chapter 6 Chemical Bonding"— Presentation transcript:

1 Modern Chemistry Chapter 6 Chemical Bonding
Sections 1-5Introduction to Chemical BondingCovalent Bonding & Molecular CompoundsIonic Bonding & Ionic CompoundsMetallic BondingMolecular GeometryChapter 6 Section 2 Covalent Bonding... pages

2 Chapter 6 Section 2 Covalent Bonding... pages 178-189
MoleculeMolecular compoundChemical formulaMolecular formulaBond energyElectron-dot notationLewis StructureStructural formulaSingle bondMultiple bondResonanceChapter VocabularyChapter 6 Section 2 Covalent Bonding... pages

3 Covalent Bonding and Molecular Compounds
Section 2Covalent Bonding and Molecular CompoundsChapter 6 Section 2 Covalent Bonding... pages

4 Chapter 6 Section 2 Covalent Bonding... pages 178-189
MoleculesA neutral group of atoms that are held together by covalent bondsHas all the physical and chemical properties of the compoundMay consist of two or more atoms of the same elementDiatomic elements I2 Br2 Cl2 F2 O2 N2 H2 Molecular elements S8 P4I Bring Clay For Our New House & Swimming Pool.Chapter 6 Section 2 Covalent Bonding... pages

5 Chapter 6 Section 2 Covalent Bonding... pages 178-189
FormulasChemical Formula – indicates the relative numbers of atoms of each kind in a chemical compound by using symbols and numeric subscriptsMolecular Formula – shows the types and number of atoms in a single moleculeChapter 6 Section 2 Covalent Bonding... pages

6 Chemical Formula Animation
Chapter 6 Section 2 Covalent Bonding... pages

7 Formation of Covalent Bonds
p. 179Chapter 6 Section 2 Covalent Bonding... pages

8 Formation of a Covalent Bond
Forces to considerElectrons repel each otherProtons and electrons attract each othere- to p+ attraction is greater than the e- to e- repulsionChapter 6 Section 2 Covalent Bonding... pages

9 Formation of a Covalent Bond
Potential Energy and StabilityHigh P.E. is related to low stabilityLow P.E. is related to high stabilityChapter 6 Section 2 Covalent Bonding... pages

10 Bond Length & Stability
p. 179Chapter 6 Section 2 Covalent Bonding... pages

11 Characteristics of Covalent Bonds
Bond Length – the distance between two bonded atoms at their minimum potential energyEnergy is released when a bond formsThe same amount of energy is required to break that bondBond Energy – the energy required to break a chemical bond and form neutral atoms.Chapter 6 Section 2 Covalent Bonding... pages

12 Bond Energy & Length Table
p. 182Chapter 6 Section 2 Covalent Bonding... pages

13 Chapter 6 Section 2 Covalent Bonding... pages 178-189
Bond Length AnimationChapter 6 Section 2 Covalent Bonding... pages

14 Chapter 6 Section 2 Covalent Bonding... pages 178-189
Bond Energy Animationp. xxChapter 6 Section 2 Covalent Bonding... pages

15 Noble Gas Configuration
p. 183Chapter 6 Section 2 Covalent Bonding... pages

16 Chapter 6 Section 2 Covalent Bonding... pages 178-189
Octet RuleChemical compounds tend to form so that each atom by gaining, losing or sharing electrons has an octet of electrons in its highest energy levelChapter 6 Section 2 Covalent Bonding... pages

17 Chapter 6 Section 2 Covalent Bonding... pages 178-189
Octet Rule ExceptionsLess than 8 electronsBoronThree valence electronsStable with only six instead of eightBerylliumTwo valence electronsStable with only four instead of eightBAlways!!BeChapter 6 Section 2 Covalent Bonding... pages

18 Chapter 6 Section 2 Covalent Bonding... pages 178-189
Octet Rule ExceptionsExpanded valence - involves the d orbitals as well as s & pPhosphorusFive valence electronsStable with only ten instead of eightSulfurSix valence electronsStable with only twelve instead of eightPNot Always!!SChapter 6 Section 2 Covalent Bonding... pages

19 Chapter 6 Section 2 Covalent Bonding... pages 178-189
Octet Rule AnimationChapter 6 Section 2 Covalent Bonding... pages

20 Lewis Structures Animation
Chapter 6 Section 2 Covalent Bonding... pages

21 Chapter 6 Section 2 Covalent Bonding... pages 178-189
Lewis StructuresFormulas in which the symbols represent nuclei and inner shell electrons, dashes or dot-pairs between symbols represent covalent bonds and dots by one symbol represent unshared pairs.Shared pairs = a bondUnshared pairs = a lone pearChapter 6 Section 2 Covalent Bonding... pages

22 Chapter 6 Section 2 Covalent Bonding... pages 178-189
Lone Pair AnimationChapter 6 Section 2 Covalent Bonding... pages

23 Chapter 6 Section 2 Covalent Bonding... pages 178-189
Structural FormulaIndicates the type, number and arrangement of the atoms and the bonds but not the unshared pairsChapter 6 Section 2 Covalent Bonding... pages

24 Structural Formula Animation
Chapter 6 Section 2 Covalent Bonding... pages

25 How to Draw Lewis Structures
1. Do the math to determine the number of bonds(1 x 8) +(3 x 2) +(1 x 8)= 22 e-C H3 I_(1 x 4) +(3 x 1) +(1 x 7)= 14 e-8 e-/2 = 4Divide the total by 2 to get the number of bonds in the molecule.Subtract the “have” from the “need”.All atoms need 8 electrons to be stable,except H which only needs 2.All atoms have their valence electrons available for bonding.Chapter 6 Section 2 Covalent Bonding... pages

26 How to Draw Lewis Structures
2. Arrange the atoms as symetrically as possible, with a central atom.HHCIHC is the central atom if it is present.H and halogens go on the outside.Chapter 6 Section 2 Covalent Bonding... pages

27 How to Draw Lewis Structures
3. Connect with bonds.HHCIHIf you have too many bonds, double or triple up.Chapter 6 Section 2 Covalent Bonding... pages

28 How to Draw Lewis Structures
4. Add unshared pairs so that all atoms have 8e- (except H)HHCIHTry page 186 #1-4 Practice.A bond counts as two electrons.Chapter 6 Section 2 Covalent Bonding... pages

29 Multiple Covalent Bonds
Single bond: 2 e- are shared by 2 atomsDouble bond: 4 e- are shared by 4 atomsTriple bond: 6 e- are shared by 3 atomsOccur commonly with C, N and OSTRONG single bond SHORTSTRONGER double bond SHORTERSTRONGEST triple bond SHORTESTTable on page 187Try page 188 #1 & 2 PracticeChapter 6 Section 2 Covalent Bonding... pages

30 Multiple Bonds Animation
p. xxChapter 6 Section 2 Covalent Bonding... pages

31 Chapter 6 Section 2 Covalent Bonding... pages 178-189
Resonance StructuresBonding in molecules that cannot be correctly represented by a single Lewis structure.Chapter 6 Section 2 Covalent Bonding... pages

32 Chapter 6 Section 2 Covalent Bonding... pages 178-189
Resonance Animationp. xxChapter 6 Section 2 Covalent Bonding... pages

33 Lewis Structures Practice
C2Cl4SCl2AsF5CI2Cl2BF3NO 1-CH2OIO3 1-Lewis Structures PracticeChapter 6 Section 2 Covalent Bonding... pages

34 Section 2 Homework Chapter 6 Section 2 Worksheet
Chapter 6 Section 2 Covalent Bonding... pages

Modern Chemistry Chapter 6

Chemical Bonding, Covalent & Molecular Compounds, Ionic Bonding & ionic Compounds, Metallic Bonding, and Molecular Geometry
a mutual electrical attraction between the nuclei and the valence electrons of different atoms that binds the atoms together
chemical bonding that results from the electrical attraction between large numbers of cations (metals) and anions (nonmetals)
chemical bonding that results from the sharing of electron pairs between 2 atoms
The difference in ___________ is a general guide for determining bonding type
electonegativity difference of 0-0.3
type of bond resulting from electronegativity difference of 0.31-1.7
type of bond resulting from electronegativity difference of 0.71-3.3
a covalent bond in which the bonding electrons are shared equally by the bonded atoms, resulting in a balanced distribution of electrical charge.
covalent bond in which the bonded atoms have an unequal attraction for the shared electrons
uneven distribution of charge
a measure of an atom's ability to attract electrons
a neutral group of atoms that are held together by covalent bonds
chemical compound whose simplest units are molecules
indicates the relative numbers of atoms of each kind in a chemical compound by using atomic symbols and numerical subscripts
indicates the types and numbers of atoms combined in a single molecule of a molecular compound
a molecule containing only 2 atoms
distance between 2 bonded atoms at their minimum potential energy
energy required to break a COVALENT bond and form neutral isolated atoms
chemical compounds tend to form so that each atom, by gaining, losing or sharing electrons, has eight electrons in its highest occupied energy level
formulas in which atomic symbols represent nuclei and inner shell electrons, dot pairs or dashes between two atomic symbols represent electron pairs in covalent bonds, and dots adjacent to only 1 atomic symbol represent unshared electrons
represented by an arrow in a Lewis structure
the bonding in molecules or ions that cannot be correctly represented by a single Lewis structure; When a double bond can attach to every atom in a Lewis structure, this displays ________.
positive and negative ions (cations and anions) that are combined so that the numbers of positive and negative charges are equal
simplest collection of atoms from which an IONIC COMPOUND formula can be established
the shape of an ionic compound
energy released when one mole of an ionic crystalline compound is formed from gaseous ions
a charged group of covalent bonded atoms
ionic compounds are only conductive when in the _______ state
electrons are free to go from atom to atom because of ___________; The reason why metals are malleable and ductile
chemical bonding resulting from the attraction between metal atoms and the surrounding sea of electrons.
the ability of a substance to be hammered or beaten into thin sheets.
the ability of a substance to be drawn, pulled, or extruded through a small opening to produce a wire.
amount of heat required to vaporize the metal (measures the strength of bonds holding metal together)
Valence-Shell Electron Pair Repulsion Theory
VSEPR Theory (give what the abbreviation stands for)
repulsion between the sets of valence-level electrons surrounding an atom causes the sets to be oriented as far apart as possible
Give the shape of ONCl or H2O
If the VSEPR Lewis structure is symmetrical, it is ___________
the force of attraction between molecules
forces of attraction between polar molecules
created by equal but opposite charges that are separated by a short distance
the intermolecular forces in which a hydrogen atom that is bonded to a highly electronegative atom is attracted to an unshared pair of electrons of an electron negative atom in a nearby molecule
the intermolecular attractions resulting from the constant motion of electrons and the creation of instantaneous dipoles; forces act between all atoms AND molecules; forces are NOT present in intramolecular forces; increases with atomic mass or molar mass.
an electron-configuration notation in which only the valence electrons of an atom of a particular element are shown, indicated by dots placed around the element's symbol.
a formula that indicates the kind, number, arrangement, and bonds but not the unshared electron pairs of the atoms in a molecule.
a covalent bond produced by the sharing of one pair of electrons between two atoms.
the mixing of two or more atomic orbitals of similar energies on the same atom to produce new orbitals of equal energies.
orbitals of equal energy produced by the combination of two or more orbitals on the same atom.
made of 1 single bond; lower energy bond than pi bonds; end to end overlap of p-orbitals
a higher energy overlapping bond (example p-orbitals overlapping side to side)
a double bond is made up of 1 sigma and 1 pi bond; a triple bond is made of 1 sigma and 2 pi bonds