G. Chem 2

  1. Phase Change:
    Image Upload 2
  2. Solids:
    • - maximum # of intermolecular forces
    • - low energy
    • - no compressibility (pressure)
    • - fixed volume + shape
  3. Liquids:
    • - some intermolecular forces
    • - higher energy
    • - very low compressibility
    • - fixed volume + shape
  4. Gases:
    • - few (almost none) intermol forces
    • - highest E
    • - compressible
    • - vol fills container
  5. Phase Change Graph:
    • Image Upload 4
    • When you add heat...
    • 1. Temp change
    • 2. Phase change
    • * ONLY one of there can occur @ a time!

    q = m C Δ T

    • q - heat
    • m - mass
    • C - specific heat capacity
    • T - temp
    • (heat takes to heat kg of subst by 1 deg Co/K every subst has own C)

    q = n Hx

    • q = heat
    • n = moles (or mass)
    • ---> Hf = heat of fusion; Hv = heat of vaporization
    • have to look @ UNITS determines n
  6. P vs. T --> phase changes
    • Image Upload 6
    • - tells what state matter something going to exist @ temp
    • - what happens through phase Δ if something stays constant
  7. P vs. T - H2O
    • Image Upload 8
    • *slope change
    • liq form = most dense form (more dense than solid form)
  8. Ideal Gas:
    • 1. Gas has no mass
    • 2. All collisions are elastic
    • - (E completely conserved; no E lost)
    • - (bounce & keep same amt of E)
    • 3. All molecules have the same E = avg energy of system
  9. Factors Affect Gases:
    • - temp (↑Ek)
    • - pressure (force of collision)
    • - volume (decr free space b/w gas mol)

    P α 1/v P α T T α V
  10. PV = n R T
    • R --> universal gas constant (always been the same)
    • [*0.0821 L•atm/K•mol (more common) or 8.31 J/k•mol (unless ask for v)]

    T --> K

    *1 mol of ideal gas = 22.4 L @STP (T → 0oc/273K; P → 1 atm)
  11. other form of PV = n R T
    • P1 V1 = P2 V2
    • T1 T2
  12. Solubility:
    ability to dissolve

    • solvent: does the dissolving
    • solute: gets dissolved
    • solution: l + s; l +l; l + g; g +g; s +s
  13. SOLUBILITY IN H2O:
    1. All grp I & ammonium (NH4+) salts are SOLUBLE

    2. NO3- (nitrate); ClO4- (perchlorate); C2H3O2- (acetate) are SOLUBLE

    3. MLS: Hg, Pb, Ag are INSOLUBLE!!!
  14. COLLIGATIVE PROPERTIES

    Van't Hoff
    i = how many parts a substance dissociates into...

    • CaCl2 → i = 3
    • NaNO3 → i = 2 (b/c NO3 covalent b.)
    • C6H12O6 → i = 1

    [anything covalent b. ONLY 1 part]
  15. Boiling Pt Elevation:
    (salt in pasta H2O)

    ∆T = K i m

    • K → boil/freeze const
    • i → van't hoff
    • m → molality
Author
Anonymous
ID
26967
Card Set
G. Chem 2
Description
G. Chem Class 2
Updated