chapter 6: bonding or a scientific drama. quick review what is a molecule? two or more atoms...
TRANSCRIPT
![Page 1: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/1.jpg)
Chapter 6: Bonding
orA Scientific Drama
Chapter 6: Bonding
orA Scientific Drama
![Page 2: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/2.jpg)
Quick ReviewQuick Review
What is a molecule? Two or more atoms joined by
bonds What is a compound?
A molecule made up of more than one kind of atom
Binary compounds: 2 atoms Ternary compounds: 3
atoms
But what is a bond?
What is a molecule? Two or more atoms joined by
bonds What is a compound?
A molecule made up of more than one kind of atom
Binary compounds: 2 atoms Ternary compounds: 3
atoms
But what is a bond?A ‘diatomic’ chlorine molecule
Buckminsterfullerene
![Page 3: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/3.jpg)
BondsBonds
Bonds hold molecules together Different types of bonds
give different properties Bond: force of attraction
between protons (nucleus) of one atom and electrons of another
Takes two electrons &
two nuclei
Bonds hold molecules together Different types of bonds
give different properties Bond: force of attraction
between protons (nucleus) of one atom and electrons of another
Takes two electrons &
two nuclei
![Page 4: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/4.jpg)
BondFormatio
n
BondFormatio
n Electron orbitals overlap and hold two electrons in place
Bonds form when attraction > repulsion
Electron orbitals overlap and hold two electrons in place
Bonds form when attraction > repulsion
![Page 5: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/5.jpg)
Making BondsMaking Bonds
Bond formation is SPONTANEOUS : System goes from high to low
energy, by releasing energy Creates stability
Bond formation is SPONTANEOUS : System goes from high to low
energy, by releasing energy Creates stability
![Page 6: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/6.jpg)
Breaking BondsBreaking Bonds
Bond breaking is
NOT SPONTANEOUS System goes from low to high
energy, needs to get that energy from somewhere else
Bond breaking is
NOT SPONTANEOUS System goes from low to high
energy, needs to get that energy from somewhere else
![Page 7: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/7.jpg)
Bonds and Energy LevelsBonds and Energy Levels
Kinetic and potential energies both decrease when bonds are formed
Kinetic and potential energies both increase when bonds are broken KE is your temperature, PE reflects that
In comparisons, more energy lost means a more stable compound Because energy out = energy in
Kinetic and potential energies both decrease when bonds are formed
Kinetic and potential energies both increase when bonds are broken KE is your temperature, PE reflects that
In comparisons, more energy lost means a more stable compound Because energy out = energy in
![Page 8: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/8.jpg)
Which kind of energy is stored in a chemical bond?
1) potential 2) kinetic
3) activation 4) ionization
As energy is released during the formation of a bond, the stability of the chemical system generally:
1) decreases
2) Increases
3) remains the same
Which kind of energy is stored in a chemical bond?
1) potential 2) kinetic
3) activation 4) ionization
As energy is released during the formation of a bond, the stability of the chemical system generally:
1) decreases
2) Increases
3) remains the same
![Page 9: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/9.jpg)
Valence ElectronsValence Electrons
Valence electrons are in the outermost energy level of an atom, so higher energy
Elements in same period have same # valence electrons, so behave similarly
Valence involved in bonding, others stay back and relax
Valence electrons are in the outermost energy level of an atom, so higher energy
Elements in same period have same # valence electrons, so behave similarly
Valence involved in bonding, others stay back and relax
![Page 10: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/10.jpg)
Major League Valence Electrons
Major League Valence Electrons
steady, reliable a little less predictable
wild, unpredictable
![Page 11: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/11.jpg)
The Octet RuleThe Octet Rule
Noble gases are inert (inactive), very stable 8 valence electrons, complete octet 8 is most electrons that can be held in valence
shell All atoms want 8, and work to get there by
interacting with others Bonding is sharing or giving/receiving
electrons Stability found in complete octet
Noble gases are inert (inactive), very stable 8 valence electrons, complete octet 8 is most electrons that can be held in valence
shell All atoms want 8, and work to get there by
interacting with others Bonding is sharing or giving/receiving
electrons Stability found in complete octet
![Page 12: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/12.jpg)
Exceptions to octet rule: H & He: only 2 electrons B & Al: will try for 8 electrons, but fine with 6 N: easy-going, can have less or more than 8 F: really electronegative, can take more than
8e-, bonds with nonmetal in Period 3 or lower Somewhat reactive noble gases (with F)
Exceptions to octet rule: H & He: only 2 electrons B & Al: will try for 8 electrons, but fine with 6 N: easy-going, can have less or more than 8 F: really electronegative, can take more than
8e-, bonds with nonmetal in Period 3 or lower Somewhat reactive noble gases (with F)
![Page 13: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/13.jpg)
![Page 14: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/14.jpg)
Lewis Electron Dot Structures
or Lewis Structures, or Lewis Diagrams
Lewis Electron Dot Structures
or Lewis Structures, or Lewis Diagrams Show valence
electrons for bonding
Chemical symbol surrounded by 1 to 8 “VE” dots
Symbol represents nucleus and non-VE, called a kernel
Show valence electrons for bonding
Chemical symbol surrounded by 1 to 8 “VE” dots
Symbol represents nucleus and non-VE, called a kernel
Two on top in S, then one at a time
![Page 15: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/15.jpg)
Draw Lewis Structures for:
K Mn Sn Al At Kr C Si Pb
Draw Lewis Structures for:
K Mn Sn Al At Kr C Si Pb
![Page 16: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/16.jpg)
![Page 17: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/17.jpg)
Important Clarification About Lewis StructuresImportant Clarification About Lewis Structures
When placing electrons dots around a chemical symbol, the first two always go on top
BUT those are simply the first 2 of however many valence electrons are present
They are counted with the valence electrons, not separate
If an atom has 1 VE, only draw 1 dot, not 2 on top and then 1
When placing electrons dots around a chemical symbol, the first two always go on top
BUT those are simply the first 2 of however many valence electrons are present
They are counted with the valence electrons, not separate
If an atom has 1 VE, only draw 1 dot, not 2 on top and then 1
![Page 18: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/18.jpg)
3 Types of Bonding3 Types of Bonding
Covalent: sharing of electrons
Ionic: giving and receiving of electrons
Metallic: distribution of electrons in metals
Covalent: sharing of electrons
Ionic: giving and receiving of electrons
Metallic: distribution of electrons in metals
![Page 19: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/19.jpg)
Types of Bonds:Covalent BondingTypes of Bonds:
Covalent Bonding
![Page 20: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/20.jpg)
Covalent bondsCovalent bonds
Covalent bonds: atoms share electrons to achieve a stable octet
2 nonmetals, same or different elements
Remember: 2 electrons per bond 8 electrons (octet) = up to 4 bonds can
be formed (with exceptions)
Single/double/triple bonds Extra electrons as lone pairs
Covalent bonds: atoms share electrons to achieve a stable octet
2 nonmetals, same or different elements
Remember: 2 electrons per bond 8 electrons (octet) = up to 4 bonds can
be formed (with exceptions)
Single/double/triple bonds Extra electrons as lone pairs
![Page 21: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/21.jpg)
Know That Lines Are Bonds!
Know That Lines Are Bonds!
7 single bonds 1 double bond & 2 single bonds
10 single bonds
Looks confusing,but same basicprinciple
![Page 22: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/22.jpg)
- Reminder -- Reminder -
Electronegativity is a measure of the attraction of a nucleus for a bonded electron; how much an atom “wants” electrons
Electronegativity is a measure of the attraction of a nucleus for a bonded electron; how much an atom “wants” electrons
![Page 23: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/23.jpg)
![Page 24: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/24.jpg)
![Page 25: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/25.jpg)
Rules for Lewis Diagrams of covalent bonds
Rules for Lewis Diagrams of covalent bonds
1. Count total # valence electrons in atoms of compound
2. Arrange atoms• Central usually has lowest
electronegativity, only present once, and isn’t H
3. Place single bonds
4. Add lone pair electrons to outsides, then center
5. Make more bonds if needed, using lone pairs
1. Count total # valence electrons in atoms of compound
2. Arrange atoms• Central usually has lowest
electronegativity, only present once, and isn’t H
3. Place single bonds
4. Add lone pair electrons to outsides, then center
5. Make more bonds if needed, using lone pairs
![Page 26: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/26.jpg)
Draw Lewis structures for:• C2H2 •Water N2 •Ammonia
Draw Lewis structures for:• C2H2 •Water N2 •Ammonia
1. Count total # valence electrons in atoms of compound
2. Arrange atoms• Central usually has lowest
electronegativity, only present once, and isn’t H
3. Place single bonds
4. Add lone pair electrons to outsides, then center
5. Make more bonds if needed, using lone pairs
![Page 27: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/27.jpg)
Draw the Lewis structure for
formaldehyde, CH2O
Draw the Lewis structure for
formaldehyde, CH2O1. Count total # valence
electrons in atoms of compound
2. Arrange atoms• Central usually has lowest
electronegativity, only present once, and isn’t H
3. Place single bonds
4. Add lone pair electrons to outsides, then center
5. Make more bonds if needed, using lone pairs
1. Count total # valence electrons in atoms of compound
2. Arrange atoms• Central usually has lowest
electronegativity, only present once, and isn’t H
3. Place single bonds
4. Add lone pair electrons to outsides, then center
5. Make more bonds if needed, using lone pairs
![Page 28: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/28.jpg)
Draw the Lewis structure for
hypobromous acid, HOBr
Draw the Lewis structure for
hypobromous acid, HOBr1. Count total # valence
electrons in atoms of compound
2. Arrange atoms• Central usually has lowest
electronegativity, only present once, and isn’t H
3. Place single bonds
4. Add lone pair electrons to outsides, then center
5. Make more bonds if needed, using lone pairs
1. Count total # valence electrons in atoms of compound
2. Arrange atoms• Central usually has lowest
electronegativity, only present once, and isn’t H
3. Place single bonds
4. Add lone pair electrons to outsides, then center
5. Make more bonds if needed, using lone pairs
![Page 29: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/29.jpg)
![Page 30: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/30.jpg)
Polarity of covalent bonds & The 1.7 “Rule”
Polarity of covalent bonds & The 1.7 “Rule”
Bond polarity is a measure of differences in electronegativity (EN)
Nonpolar covalent: share electrons evenly, with same EN, like diatoms
Polar covalent: unequal sharing of electrons, different EN, bonded atoms become “+” and “-”
Bond polarity is a measure of differences in electronegativity (EN)
Nonpolar covalent: share electrons evenly, with same EN, like diatoms
Polar covalent: unequal sharing of electrons, different EN, bonded atoms become “+” and “-”
0.0
0.1 to ~1.7-1.9
“RULE” NOT ALWAYS TRUE!
![Page 31: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/31.jpg)
1.7 Rule1.7 Rule
Electronegativity BondDifference Polarity
0.0 nonpolar covalent0.1 - 1.7 polar covalent
1.8 and up ionic
![Page 32: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/32.jpg)
![Page 33: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/33.jpg)
Which of the following bonds is the most polar in nature?
1) Cl2 2) HCl 3) HBr 4) HI
The bond in a diatomic nitrogen molecule (N2) is best described as
1) polar 2) nonpolar ionic
3) nonpolar covalent 4) polar ionic
Which of the following bonds is the most polar in nature?
1) Cl2 2) HCl 3) HBr 4) HI
The bond in a diatomic nitrogen molecule (N2) is best described as
1) polar 2) nonpolar ionic
3) nonpolar covalent 4) polar ionic
![Page 34: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/34.jpg)
Molecular SubstancesMolecular Substances
Each atom of a molecular substance has the electron configuration of a noble gas
Can be solid/liquid/gas, depending on attractive forces
Properties associated with covalent bonding: generally soft, poor conductors of heat and electricity, low melting/boiling points
Each atom of a molecular substance has the electron configuration of a noble gas
Can be solid/liquid/gas, depending on attractive forces
Properties associated with covalent bonding: generally soft, poor conductors of heat and electricity, low melting/boiling points
![Page 35: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/35.jpg)
Molecules may contain polar bonds without being polar themselves
Molecules may contain polar bonds without being polar themselves
C-O: 0.8 C-Cl: 0.6 O-H: 1.2 H-Cl: 1.0 N-H: 0.8
Symmetrical = nonpolar Asymmetrical = polar
![Page 36: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/36.jpg)
Which electron dot diagrams represent polar molecules?
Which electron dot diagrams represent polar molecules?
![Page 37: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/37.jpg)
Molecular ShapesMolecular Shapes
Linear Bent Pyramidal Tetrahedral
Remember: lone pairs influence shape!
Symmetry = nonpolar
Linear Bent Pyramidal Tetrahedral
Remember: lone pairs influence shape!
Symmetry = nonpolar
![Page 38: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/38.jpg)
One Last Note About CovalentOne Last Note About Covalent
Network solids are covalently bonded compounds without truly individual molecules
They go on forever in repeating patterns of atomic structure
Can be “divided” into unit cells, simplest representation of larger shape
Network solids are covalently bonded compounds without truly individual molecules
They go on forever in repeating patterns of atomic structure
Can be “divided” into unit cells, simplest representation of larger shape
Unit cell…
…of a net-work solid.
NOTa net-worksolid.
![Page 39: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/39.jpg)
3 Types of Bonding3 Types of Bonding
Covalent: sharing of electrons
Ionic: giving and receiving of electrons
Metallic: distribution of electrons in metals
Covalent: sharing of electrons
Ionic: giving and receiving of electrons
Metallic: distribution of electrons in metals
![Page 40: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/40.jpg)
Types of Bonds:Ionic Bonding
or“The Suspiciously
Generous Stranger”
Types of Bonds:Ionic Bonding
or“The Suspiciously
Generous Stranger”
![Page 41: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/41.jpg)
![Page 42: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/42.jpg)
Ionic BondingIonic Bonding Metal ion (+ cation) and a nonmetal ion (- anion) Positive and negative ions held together by
electrostatic attraction between opposite charges Causes high melting/boiling points,
hard/brittle substances, sometimes conductive
Metal ion (+ cation) and a nonmetal ion (- anion) Positive and negative ions held together by
electrostatic attraction between opposite charges Causes high melting/boiling points,
hard/brittle substances, sometimes conductive
![Page 43: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/43.jpg)
IonsIons Formed when individual atoms lose or gain electrons to be like the
closest noble gas Metals low EN, nonmetals high EN
Metals lose valence e- (to the nonmetal)
and become cations (+) Nonmetals gain valence e- (from the metal)
and become anions (-) Oxidation numbers represent charges formed,
and the closest noble gas
configuration
Formed when individual atoms lose or gain electrons to be like the closest noble gas
Metals low EN, nonmetals high EN Metals lose valence e- (to the nonmetal)
and become cations (+) Nonmetals gain valence e- (from the metal)
and become anions (-) Oxidation numbers represent charges formed,
and the closest noble gas
configuration
Electrons (-) charged, soNegative charge = gain electronsPositive charge = loss electrons
![Page 44: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/44.jpg)
ReminderReminder
Ionization energy: the amount of
energy needed to remove the
most loosely bound electron from a neutral
atom
-Sort of the inverse of electronegativity Metals have low IE, want to lose their electrons,
don’t put up a fight Nonmetals have high IE, want all the electrons
they can get, hold on for dear life
Ionization energy: the amount of
energy needed to remove the
most loosely bound electron from a neutral
atom
-Sort of the inverse of electronegativity Metals have low IE, want to lose their electrons,
don’t put up a fight Nonmetals have high IE, want all the electrons
they can get, hold on for dear life
![Page 45: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/45.jpg)
![Page 46: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/46.jpg)
Nonmetals gain e- & look like the closest noble gas to the right.
Metals lose e- to look like the closest previous noble gas.
![Page 47: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/47.jpg)
![Page 48: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/48.jpg)
![Page 49: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/49.jpg)
![Page 50: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/50.jpg)
Lewis Structures for ionsLewis Structures for ions
Electron loss/gain based on electronegativity values
Nonmetals pull electrons away from metals
Ions go Ions go in brackets, in brackets, with charge with charge superscriptsuperscript
Electron loss/gain based on electronegativity values
Nonmetals pull electrons away from metals
Ions go Ions go in brackets, in brackets, with charge with charge superscriptsuperscript
May use different colorsor symbols for “new”electrons
![Page 51: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/51.jpg)
Lewis Structures for IonsLewis Structures for Ions
1. Count starting valence e- for each atom
2. Add or subtract electrons for ionic charge
3. Draw Lewis structures with new total electrons
∙Metals will have none, nonmetals will have 8
·Draw nonmetals’ added e- differently than original
4. Put brackets around the ion
5. Write charge as a superscript
1. Count starting valence e- for each atom
2. Add or subtract electrons for ionic charge
3. Draw Lewis structures with new total electrons
∙Metals will have none, nonmetals will have 8
·Draw nonmetals’ added e- differently than original
4. Put brackets around the ion
5. Write charge as a superscript
Co Cr As Te Po O W2+ 3+ 3- 2- 4+ 2- 6+
Where do all the [M+]valence e- go?
![Page 52: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/52.jpg)
![Page 53: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/53.jpg)
Lewis Structures for Ionic Bonding
Lewis Structures for Ionic Bonding
1. Count starting valence e- for each atom
2. Add or subtract electrons for ionic charge
3. Draw Lewis structures with new total electrons
∙Metals will have none, nonmetals will have 8
·Draw nonmetals’ added e- differently than original
4. Put brackets around the ion
5. Write charge as a superscript
1. Count starting valence e- for each atom
2. Add or subtract electrons for ionic charge
3. Draw Lewis structures with new total electrons
∙Metals will have none, nonmetals will have 8
·Draw nonmetals’ added e- differently than original
4. Put brackets around the ion
5. Write charge as a superscript
NaCl MgO KBr PbI2
![Page 54: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/54.jpg)
Polyatomic IonsPolyatomic Ions
Polyatomic ions have multiple atoms in a charged compound.
Receives e- from elsewhere to become stable
All individual atoms are not necessarily charged
Associate with other things by ionic bonding, but held together by covalent bonds
Polyatomic ions have multiple atoms in a charged compound.
Receives e- from elsewhere to become stable
All individual atoms are not necessarily charged
Associate with other things by ionic bonding, but held together by covalent bonds
![Page 55: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/55.jpg)
Lewis Structures for Polyatomic Ions
Lewis Structures for Polyatomic Ions
-Polyatomic ions are held together by covalent bonds, but interact with other things by ionic bonding
Combined rules
1.Count all valence electrons, plus or minus any charge
*Add for (-), subtract for (+)
2.Follow steps for covalent
bonding
3.Add brackets and
superscript like ionic bonds
-Polyatomic ions are held together by covalent bonds, but interact with other things by ionic bonding
Combined rules
1.Count all valence electrons, plus or minus any charge
*Add for (-), subtract for (+)
2.Follow steps for covalent
bonding
3.Add brackets and
superscript like ionic bonds
NO3 PO4- 3- - NH4
+ClF2
+HSO4
![Page 56: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/56.jpg)
1.7 +
0.0
0.1-1.6
![Page 57: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/57.jpg)
![Page 58: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/58.jpg)
3 Types of Bonding3 Types of Bonding
Ionic: giving and receiving of electrons
Covalent: sharing of electrons
Metallic: distribution of electrons in metals
Ionic: giving and receiving of electrons
Covalent: sharing of electrons
Metallic: distribution of electrons in metals
![Page 59: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/59.jpg)
Metallic BondsMetallic Bonds
Metals: few valence electrons and low ionization energies
Can mix, but don’t bond with
other metals Atoms fixed in crystalline lattice Valence e- in a “sea of mobile
electrons” Metallic bonds: force of attraction
of mobile VE for (+) atoms Like metal ion Whack-a-Mole
Metals: few valence electrons and low ionization energies
Can mix, but don’t bond with
other metals Atoms fixed in crystalline lattice Valence e- in a “sea of mobile
electrons” Metallic bonds: force of attraction
of mobile VE for (+) atoms Like metal ion Whack-a-Mole
![Page 60: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/60.jpg)
Metallic Bond PropertiesMetallic Bond Properties
Good heat/electric conductivity Bonds are strong: high melting and boiling
points Malleability: metals can be hammered into
shapes Atoms move to new positions, but electrons stay
mobile
Which element has a crystalline lattice throughout which electrons flow freely?
1) Bromine 2) Calcium 3) Carbon 4) Sulfur
Good heat/electric conductivity Bonds are strong: high melting and boiling
points Malleability: metals can be hammered into
shapes Atoms move to new positions, but electrons stay
mobile
Which element has a crystalline lattice throughout which electrons flow freely?
1) Bromine 2) Calcium 3) Carbon 4) Sulfur
![Page 61: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/61.jpg)
Metallic bonding animation:
http://www.youtube.com/watch?v=XHV9LzCH2KA
Metallic bonding animation:
http://www.youtube.com/watch?v=XHV9LzCH2KA
![Page 62: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/62.jpg)
Other BondsOther Bonds
Savings bonds Get stronger over
time James Bond’s
Vary in strength from one to the next
Barry Bonds Also increase in
strength, but End up much
stronger than should ever occur naturally
Savings bonds Get stronger over
time James Bond’s
Vary in strength from one to the next
Barry Bonds Also increase in
strength, but End up much
stronger than should ever occur naturally
![Page 63: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/63.jpg)
Distinguishing BetweenBond Types
Distinguishing BetweenBond Types
![Page 64: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/64.jpg)
Distinguishing BetweenBond Types
Distinguishing BetweenBond Types
-Nonmetal & nonmetal-Metal & nonmetal-Polyatomic ions & anything
![Page 65: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/65.jpg)
![Page 66: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/66.jpg)
Intermolecular ForcesIntermolecular Forces
Act between molecules, not within them like “real bonds”
Only in covalent compounds, not ionic or metal
Strong IMF give high boiling and melting points
Electrostatic attractions exist between ionic compounds
Act between molecules, not within them like “real bonds”
Only in covalent compounds, not ionic or metal
Strong IMF give high boiling and melting points
Electrostatic attractions exist between ionic compounds
![Page 67: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/67.jpg)
DipolesDipoles
Polar molecules are dipoles (two distinct ends) Opposite charges temporarily attract by
dipole-dipole forces between covalent molecules
A dipole can “persuade” a nearby molecule to become an induced dipole
Dipole moment is the strength of attraction
Polar molecules are dipoles (two distinct ends) Opposite charges temporarily attract by
dipole-dipole forces between covalent molecules
A dipole can “persuade” a nearby molecule to become an induced dipole
Dipole moment is the strength of attraction
![Page 68: Chapter 6: Bonding or A Scientific Drama. Quick Review What is a molecule? Two or more atoms joined by bonds What is a compound? A molecule made](https://reader031.vdocuments.net/reader031/viewer/2022032312/56649e245503460f94b12ad5/html5/thumbnails/68.jpg)
Hydrogen BondingHydrogen Bonding
Important enough to get its own slide Hydrogen bonds act between an H atom and
a nearby N, O, or F (3 very electronegative atoms)
Much stronger than dipole- dipole attractions Hold water molecules together, give H2O its high boiling point (high for a small molecule)
Hydrogen in polar molecules is basically a bare proton, attracted by N/O/F
Important enough to get its own slide Hydrogen bonds act between an H atom and
a nearby N, O, or F (3 very electronegative atoms)
Much stronger than dipole- dipole attractions Hold water molecules together, give H2O its high boiling point (high for a small molecule)
Hydrogen in polar molecules is basically a bare proton, attracted by N/O/F