Chem 1A Ch10

  1. Linear molecule
    The atoms lie in a straight line.
  2. Planar triaganal molecule
    A planar triangular molecule is one in which three atoms are located at the corners of a triangle and are bonded to a fourth atom that lies in the center of the triangle.
  3. Tetrahedron
    Four-sided geometric figure shaped like a pyramid with triangular faces.
  4. Tetrahedron molecule
    Is one in which four atoms, located at the vertices of a tetrahedron, are bonded to a fifth atom in the center of the structure.
  5. Trigonal bipyramid
    Consists of two triagonal pyramids (pyramids with triangular faces) that share a common base, in a trigonal bipyramid molecule, the central atom is located in the middle of triangular plane shared by the upper and lower trigonal pyramids and is bonded to five atoms that are at the vertices of the figure.
  6. Equatorial bonds
    The atoms in the triangular plane are located around the equator.
  7. Axial bonds
    The two vertical bonds pointing along the north and south axis of the sphere are 180° apart and are called axial bonds. The bond angle between an axial bond and an equatorial bond is 90°.
  8. Octahedron
    An eight-sided figure, which you might think of as two square pyramids sharing a common square base.
  9. Octahedral molecule
    • The octahedron has only six vertices, and in an octahedral molecule we find an atom in the center of the octahedron bonded to six other atoms at the vertices.
  10. VSPAR
    • Valence shell electron pair repulsion model is remarkably successful at both and is also conceptually simple. The model is based on the following idea:
    • Electron pairs (or groups of electron pairs) in the valence shell of an atom repel each other and will position themselves so that they are as possable, thereby minimizing the repulsions.
  11. Electron Domain
    The term is use to describe the space occupied by a group of electrons in the valence shell of an atom.
  12. Bonding Domain
    Contains the electrons that are shared between two atoms. Therefore, all of the electrons within a given single, double, or triple bond are considered to be in the same bonding domain. A double bond (containing 4 electrons) will occupy more space than a single bond (with only 2 electrons) but all electrons shared by the atoms occupy the same general region in space, so thay all belong to the same bonding domain.
  13. Nonbonding domain
    Contains valence electrons that are associated with a single atom. A nonbonding domain is either an unshared pair of valence electrons (called a lone pair) or, in some cases, a single unpaired electron (found in molecules with an odd number of valence electrons).
  14. What is the shape for a domain of 2?
    Linear; (180o)
  15. What is the shape for a domain of 3?
    Planer triangular; (120o)
  16. What is the shape for a domain of 4?
    Tetrahedral; (109.5o) A tetrahedron is pyramid shaped. It has 4 triangular faces and 4 corners.
  17. What is the shape for a domain of 5?
    Trigonal bipyramid; This figure consists of two 3-sided pyramids joined by sharing a common face - the triangular plane through the center.
  18. What is the shape for a domain of 6?
    Octahedral; An octahedron is an 8-sided figure with 6 corners. It consists of two square pyramids that share a common square base.
  19. What shape do you get with AX3?
    • Planar triangular (ie: BF3) [bond angle 120o]
    • AX3E0-side-2D.png
  20. What shape do you get with AX2E?
    • V-shaped (ie: SnCl2) [bond angle < 120o]
    • AX2E1-2D.png
  21. What shape do you get with AX4?
    • Tetrahedral (ie: CH4) [bond angle 109.5o]
    • AX4E0-2D.png
  22. What shape do you get with AX3E?
    • Trigonal pyramidal (ie: NH3) [Bond angle < 109.5o]
    • AX3E1-2D.png
  23. What shape do you get with AX2E2?
    • Bent: (ie: H2O) [Bond angle < 109.5o]
    • AX2E2-2D.png
  24. What shape do you get with AX5?
    • Triagonal bipyramid (ie: PCl5) [bond angle 90o / 120o]
    • AX5E0-2D.png
  25. What shape do you get with AX4E1?
    • Distorted tetrahedral or Irregular tetraghedral or Seesaw or (ie: SF4) [bond angle > 90o]
    • AX4E1-2D.png
  26. What shape do you get with AX3E2?
    • T-shaped (ie: ClF3) [bond angle < 90o ]
    • AX3E2-2D.png
  27. What shape do you get with AX2E3?
    • Linear (ie: I3-) [bond angle 180o]
    • AX2E3-2D.png
  28. What shape do you get with AX6?
    • Octahedral (ie: SF6) all bond angles are 90o.
    • AX6E0-2D.png
  29. What shape do you get with AX5E1?
    • Square Pyramidal (ie: BrF5) [bond angle >90o ]
    • AX5E1-2D.png
  30. What shape do you get with AX2?
    • Linear: 180o (ie: HgCl2) [bond angle 180o ]
    • AX2E0-2D.png
  31. What shape do you get with AX4E2?
    • Square Planar (ie: XeF4) [bond angle 90o ]
    • AX4E2-2D.png
  32. Bond dipole
    For a molecule containing three or more atoms, each polar bond has its own bond dipole which contributes to the overall dipole moment of the molecule. This happens because the bond dipoles have vector properties, with both direction and magnitude. In a molecule, the bond dipoles add as vectors do.
  33. Nonpolar molecules
    The influence of one bond dipole is canceled by the effects of the others, which causes the molecules to have net dipole moments of zero.
  34. Symmetric
    To be balanced.
  35. Dissymmetric
    An “unbalanced” structure.
  36. What is sp hybrid orbitals?
    The combination of s orbitals and p orbitals.
  37. What is a pi bond?
    A bond in which the electron density is divided between two separate regions that lie on opposite sides of an imaginary line joining the two nuclei.
  38. Summary of Sigma bonds and molecular structure
    • 1. The basic molecular framework of a molecule is determined by the arrangment of its sigma bonds.
    • 2. Hybrid orbitals are used by an atom to form its sigma bonds and to hold lone pairs of electrons.
    • 3.The number of hybrid orbitals needed by an atom in a structure equals the number of atoms to which it is bonded plus the number of lone pairs of e- in itsvalence shell.
    • 4.When there is a double bond in a molecule, it consists of one sigma bond and one pi bond.
    • 5.When there is a triple bond in a molecule, it consists of one sigma bond and two pi bonds.
  39. What shape do you get with AX2?
    Linear: 180o
  40. Lattice energy diagram
    Image Upload 1
  41. Ionization flow (generalized)
    Image Upload 2
  42. Sigma bonds
    • Overlap one another, going towards one another. ie:
    • Image Upload 3
  43. Pi bonds
    • Bond that overlap one another that are side by side. ie:
    • Image Upload 4
    • or
    • Image Upload 5
Card Set
Chem 1A Ch10
General iformation