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• Units, Conversions, Powers of 10, Prefixes• Errors: Sig Figs, Error propagation• Statistics: Normal distribution,
t-test, Q-test• Equilibrium: Constant, Ksp, KH, Kw,
separation by precipitation,acids & bases
• Titration: ve
(very) Rough outlinePart 1
See midterm 1 review
• Acids & bases - buffers• Acid-base titrations• Spectrophotometry Beer’s Law
Properties of lightAtomic spectroscopy
(very) Rough outlineFor Part 1
See midterm 1 review
SOLUBILITY PRODUCT Ksp
COMMON ION EFFECT
Ksp = [Ca2+]3[PO43-]2 = 1.0 x 10-26
= (3x)3(0.10 + 2x)2 = 1.0 x 10-26
EQUILIBRIUM
x solubility (mols/L of Ca3(PO4) that can disolve)
TITRATION
STEP 1: reaction
STEP 2: Ve
STEP 4: at equivalence
STEP 5: after equivalence
STOICH
IOMETR
Y!
STEP 3: before equivalencewhat part is left?
all analyte consumed
excess titrant
Weak acidWith Strong base
HA H+ + A-
STEP 1: reaction
STEP 2: Ve
# mols base added = # mols acid removed
Weak acidWith Strong baseSTEP 3: before equivalence
BUFFER! HA H+ + A-
NB: at v = ve/2 concentrations are equal pH = pKa !
Weak acidWith Strong baseSTEP 3: before equivalence
BUFFER!STEP 4: at equivalence
A- + H2O HA + OH- Kb
HA H+ + A-
NB: What is pH at equivalence:for titration of strong acid with strong base?and for a weak acid with a strong base > or < 7?
Weak acidWith Strong baseSTEP 3: before equivalence
BUFFER!STEP 4: at equivalence
A- + H2O HA + OH- Kb
STEP 5: after equivalence
excess OH-
HA H+ + A-
The fraction of atoms in the excited state is still less than 0.02%,but that fraction has increased by 100(1.74 – 1.67)/1.67 = 4%