ANALYTICAL CHEMISTRY FINAL- ACS EXAM
What else can we use to keep the complete half cell reaction neutral? -
ANSWERS-a semi-permeable membrane
What is one problem with the semi-permeable membranes? - ANSWERS-it cannot
be made to be 0% permeable to other cations or anions
A good semi-permeable membrane will have what type of K? - ANSWERS-the K
value will be very very small
What type of agent is used more in redox titrations as a titrant? - ANSWERS-an
oxidizing agent
What is the problem with using permanganate as a titrant in redox titrations? -
ANSWERS-it is not a primary standard
When doing a redox titration, are you able to find a point at 0 mL? - ANSWERS-no,
you cannot find a point because you don't truly know the [metal]
Doing a redox titration: - ANSWERS-1. Find the K value using the equation to find
K with half-cells
2. Find the equivalence point(same as with acid base titrations)
3. solve the ice tables (WATCH OUT FOR STOICHIOMETRY)
,4. Solve for E+ using the concentrations you got
5. Find Ecell by taking the E+ you found- E- of the reference electrode
chelate effect - ANSWERS-the ability of multidentate ligands to form more stable
metal complexes than those formed by similar monodentate ligands
masking agent - ANSWERS-a reagent that protects some component of the
analyte from reaction with the EDTA
common ion effect - ANSWERS-a salt will be less soluble if one of its constituent
ions is already present in the solution
Gravimetric factor - ANSWERS-(grams of substance in analyte)/(grams of product
formed)
what is an extraction? - ANSWERS-combine two immiscible phases (polar, non-
polar), agitate, and let the analyte partition
what is chromatography? - ANSWERS-combine two immiscible phases (polar, non-
polar), let analyte partition
what is the difference between an extraction and chromatography? - ANSWERS-
one of the phases is flowing in chromatography while the other phase is
stationary
, what is the principle of extraction? - ANSWERS-like dissolves like
Ka equation for chromatography - ANSWERS-[A]stationary phase/[A]moblie phase
In chromatography you want to have Ka and Kb - ANSWERS-not equal to each
other
Retention Factor Equation - ANSWERS-k=(tR-tM)/tM
tR is the distance between the peaks
tM is the distance from 0 to the first peak
Relative Retention - ANSWERS-alpha=k2/k1 or alpha=t'2/t'1
*the smallest it can be is 1 which is bad to get
Resolution(Efficiency) - ANSWERS-R=(tR1-tR2)/(0.5(w2+w1))
R must be greater than or equal to 0
Liquid Chromatography - ANSWERS-used for samples that are not volatile, like
dissolves like
Normal Phase in Liquid Chromatography - ANSWERS-a more polar stationary
phase and less polar mobile phase and is not used as often
What else can we use to keep the complete half cell reaction neutral? -
ANSWERS-a semi-permeable membrane
What is one problem with the semi-permeable membranes? - ANSWERS-it cannot
be made to be 0% permeable to other cations or anions
A good semi-permeable membrane will have what type of K? - ANSWERS-the K
value will be very very small
What type of agent is used more in redox titrations as a titrant? - ANSWERS-an
oxidizing agent
What is the problem with using permanganate as a titrant in redox titrations? -
ANSWERS-it is not a primary standard
When doing a redox titration, are you able to find a point at 0 mL? - ANSWERS-no,
you cannot find a point because you don't truly know the [metal]
Doing a redox titration: - ANSWERS-1. Find the K value using the equation to find
K with half-cells
2. Find the equivalence point(same as with acid base titrations)
3. solve the ice tables (WATCH OUT FOR STOICHIOMETRY)
,4. Solve for E+ using the concentrations you got
5. Find Ecell by taking the E+ you found- E- of the reference electrode
chelate effect - ANSWERS-the ability of multidentate ligands to form more stable
metal complexes than those formed by similar monodentate ligands
masking agent - ANSWERS-a reagent that protects some component of the
analyte from reaction with the EDTA
common ion effect - ANSWERS-a salt will be less soluble if one of its constituent
ions is already present in the solution
Gravimetric factor - ANSWERS-(grams of substance in analyte)/(grams of product
formed)
what is an extraction? - ANSWERS-combine two immiscible phases (polar, non-
polar), agitate, and let the analyte partition
what is chromatography? - ANSWERS-combine two immiscible phases (polar, non-
polar), let analyte partition
what is the difference between an extraction and chromatography? - ANSWERS-
one of the phases is flowing in chromatography while the other phase is
stationary
, what is the principle of extraction? - ANSWERS-like dissolves like
Ka equation for chromatography - ANSWERS-[A]stationary phase/[A]moblie phase
In chromatography you want to have Ka and Kb - ANSWERS-not equal to each
other
Retention Factor Equation - ANSWERS-k=(tR-tM)/tM
tR is the distance between the peaks
tM is the distance from 0 to the first peak
Relative Retention - ANSWERS-alpha=k2/k1 or alpha=t'2/t'1
*the smallest it can be is 1 which is bad to get
Resolution(Efficiency) - ANSWERS-R=(tR1-tR2)/(0.5(w2+w1))
R must be greater than or equal to 0
Liquid Chromatography - ANSWERS-used for samples that are not volatile, like
dissolves like
Normal Phase in Liquid Chromatography - ANSWERS-a more polar stationary
phase and less polar mobile phase and is not used as often
