Term | Definition |
qualitative analysis | identifying what is in an unknown |
wavelength→→ | crest- to- crest distance between waves |
Vollhard titration | formation of a soluble |
aliquot factor | portion of total solution |
desiccant | drying agent in dessicator |
weight percent | weight solute/ mL sample |
argentometric titration | titrations iinvolving Ag+ |
molar absorptivity | symbolized by epsilon |
confidence interval | range of values in which there is a specified probability of finding the true mean |
Na2CO3 and THAM | the fraction of incident light that passes through a sample T=(P/Po) |
density | m/v |
direct titration | a way to determine the contents of a substance quantitatively. |
multidentate ligand | binds to the metal ligand through more than one ligand atom |
quantitative analysis | identifying how much is present |
Chelate | compound containing a ligand (typically organic) bonded to a central metal atom at two or more points |
monodentate ligand | ligand that bonds to a metal ion through only one atom |
gravimetric analysis | mass of product is measured to determine how much unknown was present |
direct weighing | place directly on balance |
aliquot factor | portion of total solution |
KHP | bases |
absorbance spectrum → | graph showing how A (or epsilon) varies with wavelength
Beer's law→ |
student’s t test | statistical tool used to express confidence intervals and to compare results from different experiments |
wavelength | crest- to- crest distance between waves |
F test | to test if variances from two things are equal |
absorbance spectrum | graph showing how A (or epsilon) varies with wavelength |
direct titration | way to determine the contents of a substance quantitatively |
Kjeldahl Nitrogen determination | one of the most widely used methods for determining |
iodometry | titration Of iodine produced when oxidizing analyte is added to excess I- |
systematic error | error in process or equipment |
relative error relative uncertainty? | (Absolute uncertainty/magnitude of measurement) |
standardization | titrating to determine concentration of titrant |
volumetric analysis | volume of known reagent required for complete reaction with analyte by a known reaction is measured |
pipet | used to transfer known amount of liquid- can go to 4 s.f. |
Aliquot | portion that represents a whole |
precision | reproducibility of replicate deliveries |
precision | reproducibility of replicate deliveries |
indicator error | dif btwn observed and true equivalence point |
determinate error | repeatable if measurement made same way (correctable) |
meniscus | curvature of liquid caused by surface tension |
gravimetric analysis | mass of product is measured to determine how much unknown was present |
indeterminate error | (random error)- from experiment |
back titration | excess of a standard reagent is added to analyte |
degrees of freedom | (n-1) |
transmittance | the fraction of incident light that passes through a sample TEquals(P/Po) |
Grubbs test | test for an outlier |
analyte | substance that is undergoing analysis (substance being measured) |
accuracy | difference between delivered and desired volume |
buret | used to titrate |
relative precision (rsd) | measurement of how close measurements are to each other |
volumetric flask | calibrated to contain certain vol of liquid at 20 degrees celcius when bottom of meniscus in in the right spot |
Aliquot | portion that represents a whole |
Fajans titration | adsorption of a colored indicator on the precipitate at the end point |
spectrophotometry→ | the use of electromagnetic radiation to measure chemical concentrations |
complexometric titration | for of volumetric analysis in which the formation of a colored complex is used to indicate the endpoint of a titration |
quantitative analysis | identifying how much is present |
analytical balance | measure to 4 decimal places |
top-loading balance | measures to 2 decimal places |
hygroscopic | absorbs/ attracts moisture from air |
buret | used to titrate→ goes to 4 s.f. measures in mL |
desiccator | closed chamber containing drying agent—to keep samples dried |
molarity | moles solute/ L solution |
Lewis base | electron pair donors |
t statistic | ratio of the departure of an estimated parameter from its notional value and its standard error |
nitrogen in organic substances | the solid is digested in boiling sulfuric acid to convert nitrogen into ammonium |
indeterminate error | (random error)- from experiment |
indirect weighing | weigh by difference—do not weigh onto balance |
standard devation | measure of width of distribution |
Lewis base | electron pair donors |
analytical balance | measure to 4 decimal places |
indirect titration | another name for a back titration |
parallax error | error that occurs when your eye is not at the same height as the meniscus |
parallax error | error that occurs when your eye is not at the same height as the meniscus |
Gaussian distribution | characterized by a mean and standard deviation—mean is center of distribution and standard deviation is width→ (bell shaped curve) |
monodentate ligand | ligand that bonds to a metal through only one atom |
relative standard deviation | std deviation devided by mean |
Mohr titration | determination of a chloride by precipitation titration with silver nitrate |
top-loading balance | measures to 2 decimal places |
iodimetry | when a reducing analyte is titrated wIth iodine |
Beer's law | dependence on concentration and path length |
titration | increments of a known reagent are added to the analyte |
pooled standard deviation | pooled standard deviation to make use of multiple sets of data |
indirect weighing | weigh by difference—do not weigh onto balance |
indicator | compound with a property that changes abruptly when titration is complete |
standard solution | solution containing known quantity of analyte |
tare | 0 a balance |
analyte | substance that is undergoing analysis (substance being measured) |
degrees of freedom | where n is number of data points |
displacement titration | analyte is treated with excess of a second metal bound to EDTA. The analyte ion displaces the second metal from the EDTA complex |
calibration curve | absorbance at one wavelength is plotted against different concentrations in a series of standards |
titrant | known reagent solution |
Spectroscopy
Absorbance | most useful quantitity for chemical analysis (A)—higher the absorbance |
volumetric flask | calibrated to contain certain vol of liquid at 20 degrees celcius when bottom of meniscus in in the right spot |
meniscus | curvature of liquid caused by surface tension |
Ligand | atom or group of atoms bound to whatever atom you are interested in |
molecular weight | molar mass ( mass of a molecule) calculated as the sum of the mass of each constituent atom multiplied by the number of atoms of that element in the molecular formula |
calibration curve→ | absorbance at one wavelength is plotted against different concentrations in a series of standards |
cuvet | cell which has flate |
equilibrium concentration | the actual concentration |
Lewis acid | electron pair acceptor |
masking agent | prevents impurities from reacting with the precipitant |
determinate error | repeatable if measurement made same way (correctable) |
blank titration | contains everything except the analyte helps us see titration error |
student’s t test | statistical tool used to express confidence intervals and to compare results from different experiments |
Ligand | an atom or group of atoms bound to whatever atom you are interested in |
weight percent | weight solute/ mL sample |
p value | tells you if you can reject or accept your null hypothesis |
cuvet→ | cell which has flate |
pipet | used to transfer known amount of liquid- can go to 4 s.f. |
equivalence point | when the moles of titrant moles of analyte in their stoichiometric relationship |
transmittance → | |
primary standard | pure enough to weigh and use directly for number of moles |
analytical concentration | concentration when you weigh something and dissolve it |
hygroscopic | absorbs/ attracts moisture from air |
primary standard acids and bases | acid |
Lewis acid | electron pair acceptors |
adsorption indicator | used in Fajans titration |
confidence interval | range of values in which there is a specified probability of finding the true mean |
complexometric titration | is a form of volumetric analysis in which the formation of a colored complex is used to indicate the end point of a titration. |
accuracy | difference between delivered and desired volume |
direct weighing | place directly on balance |
Chelate | a compound containing a ligand (typically organic) bonded to a central metal atom at two or more points. |
variance | square of the standard deviation |
density | m/v |
spectrophotometry | the use of electromagnetic radiation to measure chemical concentrations |
titration error | difference between endpoint and equivalence point |
Gaussian distribution | characterized by a mean and standard deviation—mean is center of distribution and standard deviation is width (bell shaped curve) |
molarity | moles solute/ L solution |
displacement titration | Here the analyte is treated with an excess of a second metal bound to EDTA. The analyte ion displaces the second metal from the EDTA complex |
analytical concentration | concentration when you weigh something and dissolve it→ the total number of moles in |
desiccator | closed chamber containing drying agent—to keep samples dried |
end point | sudden change in physical property of solution |
tare | 0 a balance |
multidentate ligand | binds to the metal ligand through more than one ligand atom |
Absorbance→ | most useful quantitity for chemical analysis (A)—higher the absorbance |
equilibrium concentration | the actual concentration |
desiccant | drying agent in dessicator |
formation constant | equilibrium constant for reaction of a metal with a ligand. Also called stability constant |
molar absorptivity→ | symbolized by epsilon |
molecular weight | molar mass ( mass of a molecule) calculated as the sum of the mass of each constituent atom multiplied by the number of atoms of that element in the molecular formula |
qualitative analysis | identifying what is in an unknown |