Analytical Chemistry

Question 1

most general or top-most; physical/chemical principle

Answer 1

technique

Question 2

application of technique on specific matrix

Answer 2

method

Question 3

set of written instruction on application of method for sample

Answer 3

procedure

Question 4

most specific; set of written guidelines

Answer 4

protocols

Question 5

purity ≥ 95%

Answer 5

American Chemical Society (ACS)

Question 6

high purity; dilutions of ACS

Answer 6

Reagent or Analytical Reagent (AR)

Question 7

meets standard of US Pharmacopeia

Answer 7

USP

Question 8

meets standard of National Formulary

Answer 8

NF

Question 9

relatively high quality but unknown levels of impurity; used in general labwork when AR is not required

Answer 9

Laboratory

Question 10

low grade (purity ≤ 90%); supplied in bulk; for quality testing only

Answer 10

Technical or Commercial

Question 11

type of gravimetry where thermal or chemical energy is used to remove volatile species

Answer 11

volatilization gravimetry

Question 12

steps in gravimetry

Answer 12

weigh sample -> sample dissolution -> analyte precipitation -> digestion -> filtration and washing -> drying/ignition -> weigh residue

Question 13

Which oxides are acidic/basic?

Answer 13

• Metal oxides: basic
• Nonmetal oxides: acidic

Question 14

acid produces H+ in aqueous solution

Answer 14

Arrhenius acid

Question 15

base produces OH- in aqueous solution

Answer 15

Arrhenius base

Question 16

acid is proton donor

Answer 16

Bronsted-Lowry acid

Question 17

base is proton acceptor

Answer 17

Bronsted-Lowry base

Question 18

acid is e- pair acceptor

Answer 18

Lewis acid

Question 19

base is e- pair donor

Answer 19

Lewis base

Question 20

List the strong bases

Answer 20

OH- with Li, Na, K, Mg, Ca, Ba

Question 21

List common diprotic acid (and base)

Answer 21

sulfuric and sulfurous acid, carbonic acid, hydrogen sulfide (H2S), oxalic acid (H2C2O4), malonic acid (H2C3H2O4)

Question 22

Common tripotic acid (and base)

Answer 22

phosphoric acid (H3PO4)

Question 23

in complexation, metals act as

Answer 23

Lewis acid

Question 24

in complexation, ligands act as

Answer 24

Lewis base

Question 25

primary valence

Answer 25

oxidation state/number; charge of metal

Question 26

secondary valence; coordination number

Answer 26

number of binding ligands

Question 27

serves as sequestering agent to inactivate metal ions by binding or chelation

Answer 27

EDTA

Question 28

analyte, titrant, and indicator in Liebig method

Answer 28

alkali cyanide, silver nitrate, potassium iodide

Question 29

Ksp at 25° C

Answer 29

1.82x10^-10

Question 30

factors and their effect on solubility, s (M)

Answer 30

common ion effect (decreases), weak acid formation (increases), complex ion formation (increases)

Question 31

Volhard indicator and titrant

Answer 31

ferric alum (blood-red complex), thiocyanate

Question 32

Mohr indicator and titrant

Answer 32

potassium oxalate (red ppt), silver nitrate

Question 33

Fajans indicator and titrant

Answer 33

DCF (pink) or eosin/tetrabromofluorescein (for Br-, I-. SCN-), silver nitrate

Question 34

Iodimetry vs Iodometry

Answer 34

iodimetry - direct titration of analyte (RA) with iodine (OA); iodometry - indirect determination of analyte (RA) thru excess iodide (RA), consequently titrated with thiosulfate with starch indicator

Question 35

spontaneous reaction to produce electricity; cell potential is positive

Answer 35

voltaic/galvanic cell

Question 36

non-spontaneous reaction; cell potential is negative

Answer 36

electrolytic cell

Question 37

where oxidation occurs

Answer 37

anode in anolyte

Question 38

where reduction occurs

Answer 38

cathode in catholyte

Question 39

5 basic components of spectroscopy

Answer 39

source -> wavelength selector -> sample in cell or cuvette -> detector -> signal processor

Question 40

line vs continuum source

Answer 40

line - emits radiation over selected wavelength; continuum - over a broad range of wavelength

Question 41

filter vs monochromator

Answer 41

filter - no continuous variation of wavelength; monochromator - has continuous variation

Question 42

spectroscopy most extensively employed in quantitative analysis

Answer 42

UV-Vis

Question 43

spectroscopy for structure elucidation of inorganic and organic compounds

Answer 43

IR

Question 44

decrease in no. of photons passing through the sample; measurement of this decrease

Answer 44

attenuation; absorbance

Question 45

the plot of absorbance vs photon's energy

Answer 45

absorbance spectrum

Question 46

limitations of Beer's law (ideal)

Answer 46

monochromatic light, only transmitted light reaches the detector, one absorbing species, and dilute solution

Question 47

5 steps in mass spectroscopy

Answer 47

vaporization -> ionization -> acceleration -> deflection -> detection

Question 48

plot of intensity of each ion vs m/z ratio

Answer 48

mass spectrum

Question 49

tallest peak in spectrum

Answer 49

base peak; also known as M (molecular weight) peak in simple molecules

Question 50

other peaks in a spectrum are due to

Answer 50

fragmentation

Question 51

2 old ways of IR sample preparation

Answer 51

Nujol mull and pressed pellets - spectra of solids; thin-film cells - solution phase

Question 52

plot of transmitted light vs wavenumber

Answer 52

IR spectrum plot

Question 53

functional group region

Answer 53

has 1 or 2 bands of functional group; at 4000 to 1500 cm^-1

Question 54

fingerprint region

Answer 54

complex set of bands unique for every compound; at <1500 cm^-1

Question 55

plot of intensity vs chemical shift

Answer 55

NMR spectrum plot