CALCULATIONS USED IN ANALYTICAL CHEMISTRY Flashcards
IMPORTANT UNITS OF MEASUREMENT
SI Units of Measurement, Mass and Weight, Mole and Millimole
A standardized system of units that is based
on the seven fundamental base units
International System of Units (SI)
SI Base Unit: Mass
Kilogram
SI Base Unit:Length
Meter (m)
SI Base Unit:Time
Second (s)
SI Base Unit: Temperature
Kelvin (K)
SI Base Unit: Amount of
substance
Mole (mol)
SI Base Unit: Electric
current
Ampere (A)
SI Base Unit: Luminous
intensity
candela (cd)
Used to express small or large measured quantities
in terms of a few simple digits
PREFIXES
Wavelength yellow light
= 5.9 x 10-7 or 590 nm
(nanometers)
Volume of a liquid injected onto a chromatographic
column =
roughly 50 x 10-6 L, or 50 μL (microliters)
The amount of memory on some computer hard disks
is
around 20 x 109bytes, or 20 Gbytes (gigabytes)
In analytical chemistry, we often determine the
amount of ?
chemical species
Laboratory Reference Ranges in Healthy Adults:
Ammonia:
15-50 μmol/L
Laboratory Reference Ranges in Healthy Adults: Chloride:
95-105 mmol/L
Laboratory Reference Ranges in Healthy Adults: Copper:
70-150 μg/dL
Laboratory Reference Ranges in Healthy Adults: Creatinine:
0.8-1.3 mg/dL
Laboratory Reference Ranges in Healthy Adults: Ferritin:
12-300 ng/mL (men), 12-150 ng/mL
(women)
Laboratory Reference Ranges in Healthy Adults: Glucose:
65-110 mg/dL
Laboratory Reference Ranges in Healthy Adults: Ceruloplasmin:
15-50 mg/dL
an invariant measure of the quantity of matter
in an object
Mass
– the force of attraction between an object and
its surroundings, principally the earth
Weight
is the SI unit for the amount of a chemical
substance
Mole (mol)
Expressed as the number of entities such as atoms,
molecules, ions, electrons or other particles given by
the Avogadro’s number (6.02x10^23)
Mole (mol)
Millimole =
1/1000 of a mole
millimolar mass (mM) =
1/1000 of the molar mass.
1 mole =
1000 millimoles
is the quantitative relationship among
the amounts of reacting chemical species.
Stoichiometry
It gives us how much mass of each of the
reactants is needed in a given chemical reaction,
and the number of product/s formed.
Stoichiometry
Apparently, stoichiometry involves working in a
__________ equation.
balanced
gives the simplest whole
number ratio of atoms in a chemical compound.
EMPIRICAL FORMULA
specifies the number of
atoms in a molecule.
MOLECULAR FORMULA
is a visual representation
that shows how atoms are arranged and bonded
together in a chemical compound.
is a visual representation
that shows how atoms are arranged and bonded
together in a chemical compound.
A balanced chemical equation follows the principle
of ______________________ – “Matter is neither
created nor destroyed.”
Law of Mass Conservation
Four fundamental ways of expressing solution
concentration:
Molar/Analytical concentration
Percent concentration
Solution-diluent volume ratio
P-functions
is the number of moles that
species that is contained in 1 liter of the solution (not
1L of solvent).
MOLAR CONCENTRATION OF A SOLUTION OF A
SOLUTE SPEXIES X
gives the total number of moles of a
solute in 1 liter of the solution (or the total number of
millimoles in 1 mL).
MOLAR ANALYTICAL CONCENTRATION OF A
SOLUTION
refers to the
molar concentration of a particular species in a
solution at equilibrium
MOLAR EQUILIBRIUM CONCENTRATION OR
EQUILIBRIUM CONCENTRATION
PERCENT CONCENTRATION OF THE SOLUTION
is also expressed as parts per hundred. This can be
expressed in three ways:
weight precent (w/w), volume percent (v/v), weight/volume percent (w/v)
ppm formula
(mass of solute/mass of solution) x 10^6 ppm
ppb formula
(mass of solute/mass of solution) x 10^9 ppb
ppt formula
(mass of solute/mass of solution) x 10^3
The composition of a dilute solution is specified
in terms of the volume of a more concentrated
solution and the volume of solvent used in
diluting it.
SOLUTION-DILUENT VOLUME RATIOS
The p-value is the negative algorithm of the molar
the concentration of the species X. Formula?
pX= -log [X]
The density of a substance is its
mass per volume
(kg/L or g/mL).
d = mass/volume
density
sp.gr. = density of substance
density of water
specific gravity
