Chemical Bonding

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Chemical Bonding

• Shape Lab

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1) One structural isomer only
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i) water, H2O

• shape angular

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• END O H 3.5 2.1 1.4
• polar covalent bond
• bond dipoles exist,
• molecule is asymmetrical
• dipoles do not cancel
• molecule is polar

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ii) methane, CH4
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• Shape Tetrahedral
• END C H 2.5 2.1 0.4
• polar covalent bond
• bond dipoles exist,
• molecule is symmetrical
• the forces cancel
• molecule is non-polar

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iii) methanol, CH3OH
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• Shape Tetrahedral about C
• Angular about O
• END C H 2.5 2.1 0.4
• END C O 2.5 3.5 1.0
• END O H 3.5 2.1 1.4
• all bonds are polar covalent
• bond dipoles exist
• molecule is not symmetrical because different
  atoms are bonded to the C and the O is angular
• the forces do not cancel
• molecule is polar

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iv) carbon tetrachloride, CCl4
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• Shape Tetrahedral
• END C Cl 2.5 3.0 0.5
• polar covalent bond
• bond dipoles exist
• molecule is symmetrical
• the forces cancel
• molecule is non-polar

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v) ammonia, NH3
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• Shape Trigonal pyramidal
• END N - H 3.0 2.1 0.9
• polar covalent bond
• bond dipoles exist,
• molecule is asymmetrical
• dipoles do not cancel
• molecule is polar

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vi) hydrazine, N2H4
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(No Transcript)
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• Shape Trigonal pyramidal about each N
• END N - H 3.0 2.1 0.9
• END N N 3.0 3.0 0.0
• N H is polar covalent bond
• N N is covalent bond
• bond dipoles exist,
• molecule is asymmetrical
• dipoles do not cancel
• molecule is polar

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vii) hydrogen sulfide, H2S
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• Shape Angular
• END S H 2.5 2.1 0.4
• polar covalent bond
• bond dipoles exist,
• molecule is asymmetrical
• dipoles do not cancel
• molecule is polar

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viii) nitrogen triiodide, NI3
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• Shape Trigonal pyramidal
• END N - I 3.0 2.5 0.4
• polar covalent bond
• bond dipoles exist,
• molecule is asymmetrical
• dipoles do not cancel
• molecule is polar

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ix) hydrogen peroxide, H2O2
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• Shape Angular about each O
• END O H 3.5 2.1 1.4
• polar covalent bond
• bond dipoles exist,
• molecule is asymmetrical
• dipoles do not cancel
• molecule is polar

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x) chlorine, Cl2
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• Shape only 2 atoms (linear)
• END Cl Cl 3.0 3.0 0.0
• covalent bond
• no bond dipoles exist, so molecule is
• non-polar

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2) Double and triple bonds

• (use the springs)

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i) carbon dioxide, CO2
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• Shape Linear (bonded to 2 atoms with no lone
  pairs)
• END C O 2.5 3.5 1.0
• END C C 2.5 2.5 0.0
• C O is polar covalent bond
• bond dipoles exist
• molecule is symmetrical
• the forces cancel
• molecule is non-polar

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ii) nitrogen, N2
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• Shape only 2 atoms (linear)
• END N N 3.0 3.0 0.0
• covalent bond
• no bond dipoles exist
• molecule is non-polar

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iii) oxygen, O2
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• Shape only 2 atoms
• END O O 3.5 3.5 0.0
• covalent bond
• no bond dipoles exist
• molecule is non-polar

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iv) ethyne, C2H2
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• Shape Linear (each C bonded to 2 atoms with no
  lone pairs)
• END C H 2.5 2.1 0.4
• END C C 2.5 2.5 0.0
• C H is polar covalent bond,
• C - C is covalent
• bond dipoles exist
• molecule is symmetrical
• the forces cancel
• molecule is non-polar

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v) hydrogen cyanide, HCN
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• Shape Linear (C bonded to 2 atoms with no lone
  pairs)
• END C H 2.5 2.1 0.4
• END C N 2.5 3.0 0.5
• both are polar covalent bonds
• bond dipoles exist
• molecule is symmetrical but the C is bonded to 2
  different atoms
• the forces do not cancel
• molecule is polar

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vi) carbon disulfide, CS2
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• Shape Linear (bonded to 2 atoms with no lone
  pairs)
• END C S 2.5 2.5 0.0
• END C C 2.5 2.5 0.0
• both are covalent bonds
• no bond dipoles exist
• molecule is non-polar

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vii) methanal, CH2O
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• Shape Trigonal planar (bonded to 3 atoms with
  no lone pairs)
• END C O 2.5 3.5 1.0
• END C H 2.5 2.1 0.4
• both are polar covalent bonds
• bond dipoles exist
• molecule is symmetrical but the C is bonded to 2
  different atoms
• the forces do not cancel
• molecule is polar

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viii) ethene, C2H4
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• Shape Planar trigonal (each C bonded to 3
  atoms with no lone pairs)
• END C H 2.5 2.1 0.4
• END C C 2.5 2.5 0.0
• C H is polar covalent bond
• bond dipoles exist
• molecule is symmetrical
• the forces cancel
• molecule is non-polar

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3) Special Compounds
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i) beryllium hydride, BeH2
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• Shape Linear
• END Be H 1.5 2.1 0.6
• polar covalent bond
• bond dipoles exist
• molecule is symmetrical
• the forces cancel
• molecule is non-polar

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ii) boron trichloride, BCl3
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• Shape Planar trigonal
• END B Cl 2.0 3.0 1.0
• polar covalent bond
• bond dipoles exist
• molecule is symmetrical
• the forces cancel
• molecule is non-polar

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iii) phosphorus pentabromide, PBr5
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• Shape Trigonal bipyramidal
• END P Br 2.1 2.8 0.7
• polar covalent bond
• bond dipoles exist
• molecule is symmetrical
• the forces cancel
• molecule is non-polar

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iv) sulfur hexachloride, SCl6
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• Shape Octahedral
• END S Cl 2.5 3.0 0.5
• polar covalent bond
• bond dipoles exist
• molecule is symmetrical
• the forces cancel
• molecule is non-polar

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v) cyclohexane, C6H12
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• Shape Tetrahedral about each C
• END C H 2.5 2.1 0.4
• END C C 2.5 2.5 0.0
• C H is polar covalent bond C C is covalent
• bond dipoles exist
• molecule is symmetrical
• the forces cancel
• molecule is non-polar

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vi) benzene, C6H6
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• Shape Planar trigonal about each C (bonded to 3
  atoms with no lone pairs)
• END C H 2.5 2.1 0.4
• END C C 2.5 2.5 0.0
• C H is polar covalent bond
• C C is covalent
• bond dipoles exist
• molecule is symmetrical
• the forces cancel
• molecule is non-polar