drill: calculate the volume of hydrogen gas produced at -23 o c under 83.1 kpa pressure when 5.1 g...
TRANSCRIPT
Drill: Calculate the volume of hydrogen gas produced at -23oC under 83.1 kPa pressure when
5.1 g of ammonia is decomposed.
AP CHM HW•Read Chapter 7
•Review PP-15
Bonding
Types of Bonds•Ionic
•Covalent
•Metallic
Metallic Bonds•Electrons are shared by many atoms
•Electrons free to move
•Two or more metals
Metallic Compounds•Generally high MP
•Hard & lusterous
•Less brittle
•Conductors
Metallic Bonds•No debate about metallic bonds
•Easy to identify
•Will not be discussed
Ionic Bonds•Electrons are transferred from one atom to another creating (+) & (-) ions
•Metal & nonmetal
Ionic Compounds•Held together by electrostatic charge
•Very high MP
•Brittle
Covalent Bonds•Electrons are shared by two atoms
•Two nonmetals
•Weaker than ionic
Covalent Compounds•Low MP
•Two nonmetals
•Flexible
•Some exceptions
Network Covalent or
Macromolecules•VHMP
•Extremely hard
Molecule•Any compound
that can exist as an entity by itself
Distinguishing Bonds•Distinguishing ionic & covalent bonds can be difficult, but generally determined by differenceelectronegativity
Bonds Types•Ionic
•Polar covalent
•Non polar covalent
Bond Types• Ionic: EN > 1.5-1.8
• Covalent: EN < 1.5-1.8
• Polar Covalent: 0.5<EN<1.5
• Non polar covalent :EN< 0.5
• Nothing is absolute
Coordinate Covalent Bonds
• A covalent bond in which the two electrons
are donated by one atom
Classify Bonds•Na-F H-Cl
•C-O Mg-O
•Fe-Fe
Dipole•Polar bonds
•Polar molecules
DipoleH F+ -
Ionic Bonding
-
+
Covalent Bonding
Occurs when electron orbitals
overlap
Homework•Work problems 47, 49, & 51 on pages 204 & 205
List & describe the three types
of bonds
OrbitalsOn the board
Max 2 e- per orbital
Hybridization•When s, p, and/or d orbitals (electron clouds) mix to make a new type of multi-lobed orbital
Hybrid Orbitals•sp dsp3
•sp2 d2sp3
•sp3
Homework•Work problems 53, 55, 57, & 59 on page 205
Drill: List 5 types of hybrid orbitals,
then give the geometric shapes &
bond angles
Electron Cloud Repulsion
• In molecules each electron cloud repels other clouds enough to spread as far apart as possible
VSEPR•Valance Shell Electron Pair Repulsion
•Electron pairs repel each other to spread out as much as possible
Bonding OrbitalsType Hybrid VSEPR• 2 lobes sp AX2
• 3 lobes sp2 AX3
• 4 lobes sp3 AX4
• 5 lobes dsp3 AX5
• 6 lobes d2sp3 AX6
Look at the diagrams on pages 186 & 190
to see diagrams of the VSEPR theory or
hybridization theory.
VSEPR Orbitals
Bonding Orbital Shape• 2 lobes: Linear 180o
• 3 lobes: Trigonal planar 120o
• 4 lobes: Tetrahedral 109.5o
• 5 lobes: Hexahedral 120&180o
• 6 lobes: Octahedral 90&180o
Drill: Calculate the density SO2 at 47oC under 83.1
kPa Pressure:
CHM II HW•Read: Chapter 7
•Problems: 7, 10, 35, & 37
•Page: 300 & 301
Types of Bonds•Ionic
•Covalent
•Metallic
Draw the Bonding Electron Dot
Diagrams for Each Element
Bonding Electron Dot Diagrams
•Electron dot diagrams that go through 4 singles before any electrons are paired up
1A: 1 single2A: 2 singles3A: 3 singles4A: 4 singles 5A: 1 pair & 3 singles6A: 2 pair & 2 singles7A: 3 pair & 1 single8A: 4 pair
Drill: Equate each of the following:
sp3 AX2 2 lobes
sp AX3 4 lobes
dsp3 AX4 6 lobes
sp2 AX5 3 lobes
d2sp3 AX6 5 lobes
Lewis Dot Diagrams
•Representation of valence electrons and bonds in a molecule or polyatomic ion
Drawing LDDsDraw the bonding electron dot
diagram for each element in the molecule with the element with the most unpaired e- near the center
Drawing LDDs• If there is more than one carbon, connect the carbons by connecting single dots between one carbon & another
Drawing LDDs• Connect a single dot on
one atom to a single dot on another (never two on the same atom)(never connect one dot to more than one other dot)
Drawing LDDs•Repeat connecting the dots until all singled dots are connected making sure to obey the octet rule if possible
Drawing LDDs• Recognize polyatomic ions
•H2CO3: CO3-2 is a
polyatomic ion; thus, the three Os must connect to the C
Drawing LDDs•Redraw the molecule neatly making sure to include all dots
Draw LDDs for:•BeCl2 H2O
•BF3 C2H6
•CH4 C3H6
•NH3 CH2O
AP Homework•Work problems 1 & 19 on pages 202 & 203
Chm II Homework•Work problems 9, 10, 35, & 37 on page 301
Lab 07 on Atomic & Molecular
Orbitals will be done tomorrow.
Drill: Draw the LDD for:
C4H8
H2CO3
Drill: Draw LDDs for:•H2C2O4
•C4H6
Coordinate Covalent BondA covalent bond in which both electrons are donated by one
atom
Draw LDDs for:
SO4-2
SO2
AP CHM HW•Work problem 23 on page 203.
CHM II HW•Work problem 36 & 41 on page 301.
Resonance Structures
Equally valid Lewis Dot Diagrams for molecule
or polyatomic ion.
OO N O
OO N O
-1 -1
Draw LDDs:HNO3
C4H5NO
Drill: Draw LDDs for:
•PH3 PO3-3
•HCN C4H8O
Expanded Octets•Sometimes atoms can be surrounded by more than 8 electrons
• Columns 5A-8A
If more atoms are bound to the central
atom than its unpaired electrons,
then split some paired electrons
Example: 5 things bound to P
P P
HintWhen drawing expanded LDDs for polyatomic ion, adjust the charge of the central atom
Draw LDDs for:
•PH5
•SCl5-1
Homework•Work problem 4, 6, 31, 41, 51, & 53 on page 203 - 205.
Drill: Draw LDDs:
•SiF6-2
•XeF4
Drill: Draw LDDs:
• ICl3
• IF4+1
Drill: Draw LDDs:
•P3O10-5 SCl5
-1
•K2SO4 C5H8O
Draw LDDs for:
CO2 H2O
CO3-2
C2H6O
Homework•Work problem 33 & 35 on page 204
•Predict all
Draw LDDs for:
•PO4-3 P2O7
-4
•K2SO4 C5H8O
Drill: Draw LDDs for:
C4H6O SCl2
C3H6O2 SiOF2
Draw LDDs for:BeH2 AlCl3 SO2
CF4 NH3 H2O
Hybridizations
•sp 2 lobes
•sp2 3 lobes
•sp3 4 lobes
Bond Angles
•sp ~180o
•sp2 ~120o
•sp3 ~109.5o
Sigma Bonds()• End to end orbital overlap
• All single bonds are sigma bonds
• All multiple bonds contain one sigma bond
Pi Bonds ()•Side by side orbital overlap
•Multiple bonds contain bonds
Multiple Bonds•Double: 1 & 1
•Triple: 1 & 2
AP Homework•Work problems 67, 71 on page 205
AP Homework•Problem 17 & 19
Page 203
Drill: Predict the type hybridization & VSEPR type for central atoms
containing 2, 3, 4, 5, or 6 lobes of electron clouds
Drill: Draw LDDs for:
H2SO4 SCl4
C3H6O2 XeF3-1
Molecular Orbital Theory• Count valence e-s• Draw orbital diagram (s & p e-s)• Draw bonding & anti-bonding Os• Fill in the chart with total # of e-s• Add the total bonding &
antibonding orbital to get bond order
X Y
2p_ _ _
2s_
_ _ _2p
_2s
Each line represents an orbital that can contain up to two electrons
X Y
2p_ _ _
2s_
_ _ _2p
_2s
2p _ _ _ anti-bonding
2p _ _ _ bonding2s _ anti-bonding
2s _ bonding
Determine the Bond Order of N2
•Each N has 5 valence e-s
•The total valence e-s = 10
N N
2p_ _ _
2s_
_ _ _2p
_2s
2p _ _ _
2p _ _ _2s _
2s _
N N
2p_ _ _
2s_
_ _ _2p
_2s
2p _ _ _
2p _ _ _2s _
2s _
N N
2p_ _ _
2s_
_ _ _2p
_2s
2p _ _ _
2p _ _ _2s _
2s _
N N
2p_ _ _
2s_
_ _ _2p
_2s
2p _ _ _
2p _ _ _2s _
2s _
N N
2p_ _ _
2s_
_ _ _2p
_2s
2p _ _ _
2p _ _ _2s _
2s _
N N
2p_ _ _
2s_
_ _ _2p
_2s
2p _ _ _
2p _ _ _2s _
2s _
N N
2p_ _ _
2s_
_ _ _2p
_2s
2p _ _ _
2p _ _ _2s _
2s _
N N
2p_ _ _
2s_
_ _ _2p
_2s
2p _ _ _
2p _ _ _2s _
2s _
N N
2p_ _ _
2s_
_ _ _2p
_2s
2p _ _ _
2p _ _ _2s _
2s _
N N
2p_ _ _
2s_
_ _ _2p
_2s
2p _ _ _
2p _ _ _2s _
2s _
N N
2p_ _ _
2s_
_ _ _2p
_2s
2p _ _ _
2p _ _ _2s _
2s _
4 bonding –1 antibonding
Bond Order of N2 = 3
Determine the bond order of:
H2 He2 O2
F2 CO Xe2
Drill: Draw the LDD & predict all for:
SO4-2
SCl4
Intermolecular Forces• Weak temporary
attractions between atoms from one molecule to another or another part of a larger molecule
Intermolecular Forces• Hydrogen-bond
• Dipole-dipole
• Dipole-induced dipole
• London dispersion forces
Hydrogen Bond• Strongest of the
intermolecular forces
• Occurs when H is bound to one highly EN element & connects to another
Dipole-Dipole•When two polar molecules connect
Dipole-Induced Dipole
•When a polar molecule gets near a non-polar one, it induces the non-polar one to become polar; thus, they connect
London Dispersion• Instantaneous attraction
for fractions of seconds in which non-polar molecules connect
• Very weak force
Draw Lewis Dot Diagram for:
ICl5
Determine: bond s, hybridization, VSEPR, & shape
Drill: Draw the bonding electron dot diagrams
for one element in each of the columns that go to the top of the chart.
Identify as ionic, covalent, or metallic bonds
Na-Cl Fe-CrS-Cl H-Cl
Mg-S C-CN-O Fe-Fe
Draw LDDs for:
HONO H3PO4
CO2 C3H4O2
Draw LDDs & Predict All for:
CF4 NH3
BF3 CO2
SeCl4 XeF4
Draw LLDs & Predict All For:
H3PO4 ICl5
IF3 CO
SeCl4 C4H6O2
Draw LDDs & predict VSEPR, Hybridization,
bond s, & shape of:
XeF4 SCl4
XeO4
List & describe the four types of intermolecular
forces
Draw Lewis Dot Diagrams of:
C4H5NO2