CHEMICAL BONDING IONIC BONDS COVALENT BONDS HYDROGEN BONDS METALLIC BONDS.

  • Published on
    16-Dec-2015

  • View
    231

  • Download
    7

Embed Size (px)

Transcript

  • Slide 1
  • CHEMICAL BONDING IONIC BONDS COVALENT BONDS HYDROGEN BONDS METALLIC BONDS
  • Slide 2
  • Slide 3
  • IONIC BONDING When an atom of a nonmetal takes one or more electrons from an atom of a metal so both atoms end up with eight valence electrons
  • Slide 4
  • IONIC BONDING IS THE COMPOUND AN IONIC COMPOUND?METAL NONMETAL SUBSCRIPTS
  • Slide 5
  • IONIC BOND FORMATION Neutral 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.
  • Slide 6
  • IONIC BONDING ION any atom with more or less electrons that it is supposed to have* *Remember that the number of electrons is supposed to be equal to the number of Protons if the atom has a neutral charge
  • Slide 7
  • IONIC BONDING Metals will tend to lose electrons and become POSITIVE CATIONS Normal sodium atom loses one electron to become sodium ion
  • Slide 8
  • IONIC BONDING Nonmetals will tend to gain electrons and become NEGATIVE ANIONS Normal chlorine atom gains an electron to become a chloride ion
  • Slide 9
  • Na +1 is called a sodium ion The +1 symbol means it has lost one electron IONIC BONDING
  • Slide 10
  • Mg +2 is called a magnesium ion The +2 symbol means it has lost two electron IONIC BONDING
  • Slide 11
  • S -2 is called a sulfide ion The -2 symbol means it has gained two electron IONIC BONDING
  • Slide 12
  • Cl -1 is called a chloride ion The -1 symbol means it has gained one electron IONIC BONDING
  • Slide 13
  • POLYATOMIC IONS--a group of atoms that act like one ion NH 4 +1 --ammonium ion CO 3 -2 --carbonate ion PO 4 -3 --phosphate ion IONIC BONDING
  • Slide 14
  • POLYATOMIC IONS ACT JUST LIKE ANY OTHER NEGATIVE ION WHEN BONDING IONIC BONDING
  • Slide 15
  • SODIUM SULFATE
  • Slide 16
  • IONIC BONDING
  • Slide 17
  • Properties of Ionic Compounds Crystalline 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.
  • Slide 18
  • Crystalline structure + + ++ + + + + + - - - - - - - - - The POSITIVE CATIONS stick to the NEGATIVE ANIONS, like a magnet.
  • Slide 19
  • 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. First get them to 800C. Dissolved in water they conduct.
  • Slide 20
  • Ionic solids are brittle +-+- + - +- +-+- + - +-
  • Slide 21
  • + - + - + - +- +-+- + - +- Strong Repulsion breaks crystal apart.
  • Slide 22
  • Slide 23
  • COVALENT BONDING When an atom of one nonmetal shares one or more electrons with an atom of another nonmetal so both atoms end up with eight valence electrons
  • Slide 24
  • COVALENT BOND FORMATION When one nonmetal shares one or more electrons with an atom of another nonmetal so both atoms end up with eight valence electrons
  • Slide 25
  • COVALENT BONDING IS THE COMPOUND A COVALENT COMPOUND?NONMETAL NONMETAL YES since it is made of only nonmetal elements
  • Slide 26
  • Covalent bonding Fluorine has seven valence electrons F
  • Slide 27
  • Covalent bonding Fluorine has seven valence electrons A second atom also has seven FF
  • Slide 28
  • Covalent bonding l Fluorine has seven valence electrons l A second atom also has seven l By sharing electrons FF
  • Slide 29
  • Covalent bonding l Fluorine has seven valence electrons l A second atom also has seven l By sharing electrons FF
  • Slide 30
  • Covalent bonding l Fluorine has seven valence electrons l A second atom also has seven l By sharing electrons FF
  • Slide 31
  • Covalent bonding l Fluorine has seven valence electrons l A second atom also has seven l By sharing electrons FF
  • Slide 32
  • Covalent bonding l Fluorine has seven valence electrons l A second atom also has seven l By sharing electrons FF
  • Slide 33
  • Covalent bonding l Fluorine has seven valence electrons l A second atom also has seven l By sharing electrons l Both end with full orbitals FF
  • Slide 34
  • Covalent bonding l Fluorine has seven valence electrons l A second atom also has seven l By sharing electrons l Both end with full orbitals FF 8 Valence electrons
  • Slide 35
  • Covalent bonding l Fluorine has seven valence electrons l A second atom also has seven l By sharing electrons l Both end with full orbitals FF 8 Valence electrons
  • Slide 36
  • Single Covalent Bond A 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 which atom the electrons moved from or to.
  • Slide 37
  • How to show how they formed Its like a jigsaw puzzle. I have to tell you what the final formula is. You put the pieces together to end up with the right formula. For example- show how water is formed with covalent bonds.
  • Slide 38
  • Water H O Each hydrogen has 1 valence electron Each hydrogen wants 1 more The oxygen has 6 valence electrons The oxygen wants 2 more They share to make each other happy
  • Slide 39
  • Water Put the pieces together The first hydrogen is happy The oxygen still wants one more H O
  • Slide 40
  • Water The second hydrogen attaches Every atom has full energy levels H O H
  • Slide 41
  • Multiple Bonds Sometimes atoms share more than one pair of valence electrons. A double bond is when atoms share two pair (4) of electrons. A triple bond is when atoms share three pair (6) of electrons.
  • Slide 42
  • Carbon dioxide CO 2 - Carbon is central atom ( I have to tell you) Carbon has 4 valence electrons Wants 4 more Oxygen has 6 valence electrons Wants 2 more O C
  • Slide 43
  • Carbon dioxide Attaching 1 oxygen leaves the oxygen 1 short and the carbon 3 short O C
  • Slide 44
  • Carbon dioxide l Attaching the second oxygen leaves both oxygen 1 short and the carbon 2 short O C O
  • Slide 45
  • Carbon dioxide l The only solution is to share more O C O
  • Slide 46
  • Carbon dioxide l The only solution is to share more O C O
  • Slide 47
  • Carbon dioxide l The only solution is to share more O CO
  • Slide 48
  • Carbon dioxide l The only solution is to share more O CO
  • Slide 49
  • Carbon dioxide l The only solution is to share more O CO
  • Slide 50
  • Carbon dioxide l The only solution is to share more O CO
  • Slide 51
  • Carbon dioxide l The only solution is to share more l Requires two double bonds l Each atom gets to count all the atoms in the bond O CO
  • Slide 52
  • Carbon dioxide l The only solution is to share more l Requires two double bonds l Each atom gets to count all the atoms in the bond O CO 8 valence electrons
  • Slide 53
  • Carbon dioxide l The only solution is to share more l Requires two double bonds l Each atom gets to count all the atoms in the bond O CO 8 valence electrons
  • Slide 54
  • Carbon dioxide l The only solution is to share more l Requires two double bonds l Each atom gets to count all the atoms in the bond O CO 8 valence electrons
  • Slide 55
  • How to draw them Add up all the valence electrons. Count up the total number of electrons to make all atoms happy. Subtract. Divide by 2 Tells you how many bonds - draw them. Fill in the rest of the valence electrons to fill atoms up.
  • Slide 56
  • Examples NH 3 N - has 5 valence electrons wants 8 H - has 1 valence electrons wants 2 NH 3 has 5+3(1) = 8 NH 3 wants 8+3(2) = 14 (14-8)/2= 3 bonds 4 atoms with 3 bonds N H
  • Slide 57
  • NHH H Examples Draw in the bonds All 8 electrons are accounted for Everything is full
  • Slide 58
  • Examples HCN C is central atom N - has 5 valence electrons wants 8 C - has 4 valence electrons wants 8 H - has 1 valence electrons wants 2 HCN has 5+4+1 = 10 HCN wants 8+8+2 = 18 (18-10)/2= 4 bonds 3 atoms with 4 bonds -will require multiple bonds - not to H
  • Slide 59
  • HCN Put in single bonds Need 2 more bonds Must go between C and N NHC
  • Slide 60
  • HCN l Put in single bonds l Need 2 more bonds l Must go between C and N l Uses 8 electrons - 2 more to add NHC
  • Slide 61
  • HCN l Put in single bonds l Need 2 more bonds l Must go between C and N l Uses 8 electrons - 2 more to add l Must go on N to fill octet NHC
  • Slide 62
  • Another way of indicating bonds Often use a line to indicate a bond Called a structural formula Each line is 2 valence electrons HHO = HHO
  • Slide 63
  • Structural Examples H CN C O H H C has 8 electrons because each line is 2 electrons Ditto for N Ditto for C here Ditto for O
  • Slide 64
  • Coordinate Covalent Bond When one atom donates both electrons in a covalent bond. Carbon monoxide CO OC
  • Slide 65
  • Coordinate Covalent Bond l When one atom donates both electrons in a covalent bond. l Carbon monoxide l CO OC
  • Slide 66
  • Coordinate Covalent Bond l When one atom donates both electrons in a covalent bond. l Carbon monoxide l CO OC
  • Slide 67
  • Polar Bonds When the atoms in a bond are the same, the electrons are shared equally. This is a nonpolar covalent bond. When two different atoms are connected, the atoms may not be shared equally. This is a polar covalent bond. How do we measure how strong the atoms pull on electrons?
  • Slide 68
  • Electronegativity A measure of how strongly the atoms attract electrons in a bond. The bigger the electronegativity difference the more polar the bond. 0.0 - 0.3 Covalent nonpolar 0.3 - 1.67 Covalent polar >1.67 Ionic
  • Slide 69
  • How to show a bond is polar Isnt a whole charge just a partial charge means a partially positive means a partially negative The Cl pulls harder on the electrons The electrons spend more time near the Cl H Cl
  • Slide 70
  • Polar Molecules Molecules with ends
  • Slide 71
  • Polar Molecules Molecules with a positive and a negative end Requires 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.
  • Slide 72
  • Is it polar? HF H 2 O NH 3 CCl 4 CO 2
  • Slide 73
  • Intermolecular Forces What holds molecules to each other
  • Slide 74
  • Intermolecular Forces They are what make solid and liquid molecular compounds possible. The weakest are called van der Waals forces - there are two kinds Dispersion forces Dipole Interactions depend on the number of electrons more electrons stronger forces Bigger molecules
  • Slide 75
  • Dipole interactions Depend on the number of electrons More electrons stronger forces Bigger molecules more electrons Fluorine is a gas Bromine is a liquid Iodine is a solid
  • Slide 76
  • Dipole interactions Occur when polar molecules are attracted to each other. Slightly stronger than dispersion forces. Opposites attract but not completely hooked like in ionic solids.
  • Slide 77
  • Dipole interactions Occur when polar molecules are attracted to each other. Slightly stronger than dispersion forces. Opposites attract but not completely hooked like in ionic solids. HFHF HFHF
  • Slide 78
  • Dipole Interactions
  • Slide 79
  • Hydrogen bonding Are 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.
  • Slide 80
  • Hydrogen Bonding H H O ++ -- ++ H H O ++ -- ++
  • Slide 81
  • Hydrogen bonding H H O H H O H H O H H O H H O H H O H H O
  • Slide 82
  • MOLECULAR SHAPES OF COVALENT COMPOUNDS
  • Slide 83
  • VSepR tHEORY
  • Slide 84
  • What Vsepr means Since electrons do not like each other, because of their negative charges, they orient themselves as far apart as possible, from each other. This leads to molecules having specific shapes.
  • Slide 85
  • Things to remember Atoms bond to form an Octet (8 outer electrons/full outer energy level) Bonded electrons take up less space then un-bonded/unshared pairs of electrons.
  • Slide 86
  • Slide 87
  • Linear Number of Bonds = 2 Number of Shared Pairs of Electrons = 2 Bond Angle = 180 EXAMPLE: BeF 2
  • Slide 88
  • Trigonal Planar Number of Bonds = 3 Number of Shared Pairs of Electrons = 3 Number of Unshared Pairs of Electrons = 0 Bond Angle = 120 EXAMPLE: GaF 3
  • Slide 89
  • Bent #1 Number of Bonds = 2 Number of Shared Pairs of Electrons = 2 Number of Unshared Pairs of Electrons = 2 Bond Angle = < 120 EXAMPLE: H 2 O
  • Slide 90
  • Bent #2 Number of Bonds = 2 Number of Shared Pairs of Electrons = 2 Number of Unshared Pairs of Electrons = 1 Bond Angle = >120 EXAMPLE: O 3
  • Slide 91
  • Tetrahedral Number of Bonds = 4 Number of Shared Pairs of Electrons = 4 Number of Unshared Pairs of Electrons = 0 Bond Angle = 109.5 EXAMPLE: CH 4
  • Slide 92
  • Trigonal Pyramidal Number of Bonds = 3 Number of Shared Pairs of Electrons = 4 Number of Unshared Pairs of Electrons = 1 Bond Angle =

Recommended

View more >