1. Solids

2. Molecular Solids Covalently bound molecules held together by intermolecular forces

3. Molecular Solids Non-conductors Insoluble in water mostly Low MP & BP Held by intermolecular F

4. Intermolecular Forces Instantaneous weak forces that hold one molecule to another or to another part of itself

6. Intermolecular Forces H-bond Dipole-dipole Dipole-induced dipole London dispersion

9. Network Molecular Solids Bound by a continuous network of covalent bonds High MP, insoluble, non- conductor

10. Ionic Solids Ions or ionic compounds held together by electrostatic charge F attraction = Kq 1 q 2 /d 2

11. Ionic Solids Non-conductors as solids Conductors in solution Soluble in water mostly Very high MP & BP Brittle

12. Metallic Solids Conductors, insoluble in water mostly, high MP & BP, held by gravitational type force F attraction = Gm 1 m 2 /d 2

13. Crystal Solid Any substance that has a well defined crystal structure

14. Crystal Lattice The three dimensional arrangement of unit cells in a crystal structure

15. Unit Cell The smallest repeating unit that a crystal structure can be divided into

17. Crystal Structures CubicMonoclinic TetragonalTriclinic Orthorhombic Hexagonal Rhombohedral

18. Cubic All angles = 90 o All sides are = All faces are squares

19. Tetragonal All angles = 90 o 2 side sets are =, third  1 set of opposing squares 2 sets opposing rectangles

20. Orthorhombic All angles = 90 o all 3 side sets are  3 unequal sets opposing rectangles

21. Hexagonal All angles = 90 o or 120 o 1 set of opposing hexagons 3 sets opposing rectangles

22. Monoclinic 2 sets of angles = 90 o third set  90 o 1 set of opposing parallel 2 sets opposing rectangles

23. Triclinic No angles = 90 o 3 unequal sets of opposing parallelograms

24. Rhombohedral No angles = 90 o All sides = 3 sets of opposing congruent rhombuses

25. Simple Cube Unit cell with one atom at each vertex 1 atom/cell

26. Body Centered Cube BCC Unit cell with one atom at each vertex & one atom in the center of the cube 2 atoms/cell

28. Face Centered Cube FCC or CCP Unit cell with one atom at each vertex & one atom on each face of the cube 4 atoms/cell

30. The density of iron in its normal state of BCC is 7.86 g/mL. Calculate its density in the FCC state

31. Drill: List & describe the 7 crystal structures

32. Hydrated Crystal A solid with water in the crystal CuSO 4 *5H 2 O

33. Anhydrous Solid A crystal without water

34. Hygroscopic Crystals that absorb moisture from the air

35. Deliquescent Crystals that absorb enough moisture from the air to liquify

36. Efflorescent Crystals that give up water to the surroundings

37. Polymorphous When a single substance can have multiple crystal structures

39. Isomorphous When different substances have the same crystal structure

40. Amorphous Solid A solid w/o a well defined crystal structure Super-cooled liquid

41. Liquid Crystals Part solid & part liquid Has a well defined crystal structure in 1 or 2 but not all 3 dimensions

42. Smectic Liquid crystal that have a well defined crystal structure in 2 dimensions

43. Nematic Liquid crystals that have a well defined crystal structure in only 1 dimension

45. Liquid A substance that holds together loosely, but has no structure in any dimension

46. Solid Definite size & shape Particles vibrate about fixed points

47. Liquid Definite size but no shape Particles vibrate about moving points

48. Gas No definite size or shape Particles move at random

50. Melting Point Temperature at which the solid phase & liquid phase are at equilibrium MP & FP are equal

51. Melting Point Temperature at which the vapor pressure of a solid = the vapor pressure of its liquid phase

52. Boiling Point Temperature at which the liquid phase & gaseous phase are at equilibrium

53. Boiling Point Temperature at which the vapor pressure of a liquid = the vapor pressure of its gaseous phase or atmospheric P

54. Adhesion The attraction of particles from different substances to each other

55. Cohesion The attraction of particles of the same substance towards each other

56. Capillarity The movement of a liquid up a thin tube due to adhesion & cohesion

57. Surface Tension Pressure on the surface of a liquid caused by the uneven forces acting on the surface molecules

59. Vapor Pressure The pressure caused by the evaporated particles in the vapor above a liquid

60. Intermolecular Forces Weak temporary attractions between atoms from one molecule to another or another part of a larger molecule

62. Intermolecular Forces Hydrogen-bond Dipole-dipole Dipole-induced dipole London dispersion forces

63. Hydrogen Bond Strongest of the intermolecular forces Occurs when H is bound to one highly EN element & connects to another

64. Dipole-Dipole When two polar molecules connect

65. 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

66. London Dispersion Instantaneous attraction for fractions of seconds in which non-polar molecules connect Very weak force

68. Predict & explain the MP trends of: 1) Li, Na, K, & Rb 2) F 2, Cl 2, Br 2, & I 2 3) LiF, NaCl, KBr, & RbI

69. Phase Diagram Graphic representation of all the phases of a substance with respect to temperature & pressure

71. 1 atm 100 K400 K Approximate MP & BP:

72. Phase Diagrams

74. Describe conditions at each number

75. Define solids, liquids, gases, melting & Boiling points

76. Determine the phase changes for the 3 arrows:

77. PHASE DIAGRAM