Analytical Chemistry: Introduction Flashcards
Branch of science that deals with the separation, identification and determination of the components in a sample
Analytical Chemistry
particularly concerned with the questions of “what chemicals are present, what are their characteristics and in what quantities are they present?”
Analytical Chemistry
is a method of analytical chemistry which seeks to find elemental composition of inorganic compounds and the functional group of organic compounds.
Qualitative Analysis
in analytical chemistry, the measurements of quantities of substances produced in reactions rather than simply noting the nature of the reactions
Quantitative Analysis
means to discover through experimentation or examination
Ascertainment of impurities
Classification of Analysis
I. Based on sample size
II. Based on the extent of determination
III. Based on nature of methods
IV. Based on materials used
< 1 mg
Ultramicroanalysis
1 mg – 10 mg
Microanalysis
10 mg – 100 mg
Semi-microanalysis
100 mg – 1 g
Macroanalysis
total amount of a class or a group of active plant principles in a given sample
Proximate analysis
Amount of a specific constituent or a single chemical species present in the sample
Ultimate analysis
also known as general/ chemical/ wet/ stoichiometric method
Classical method
-more accurate
-based on specific physical or chemical properties of the analyte
Instrumental method
Involves the crude drugs and other natural products
Miscellaneous or special method
titrimetric method
Chemical
instruments and special apparata
Physical
use of microorganism and animals and parts thereof
Biological
Types of Quantitative Analysis
A. Volumetric Analysis
B. Gravimetric Analysis
C. Special Methods
D. Physico-Chemical Methods
analysis involving the measurement of volume of a solution of know concentration required to react with the desired constituent.
Volumetric Analysis
Divisions of volumetric analysis
I. Neutralization
II. Precipitation
III. Compleximetry
IV. Oxidation
reduction permanganate ceric sulfate iodometry iodimetry bromine potassium iodate diazotization assay with nitrite
Oxidation
Analysis involving the accurate measurement of weight of substance being determined which may be isolated in pure form or converted to another substance of known composition by making it react quantitatively with another substance usually a precipitant.
Gravimetric Analysis
analysis which require a distinct type of technique such as analysis of crude drugs, assay of fats and fixed oils, assay of volatile oils and assay of alkaloids.
Special Methods
Analysis based on some specific physical or chemical property or properties of the substance being analyzed with the use of instruments such as: spectrophotometer, chromatograph units, polarographer, polarimeter, flourometer.
Physico-Chemical Methods
determination of alcohol, protein components, volatile component, alkaloids
Distillation
physical characterization
Microscopy
rotatory power
Polarimeter
purity of substance
Refractometer
moisture content
Dessicator
moisture content
-Oven
-Moisture Balance
identity and quantity of component
-Chromatography
identity and purity
Spectroscopy
quality and quantity of components
Polarography
determination of amounts required to produce the desired, definite effect
Biological tests
According to their properties, cations are usually classified into five groups.
Detecting Cations
-Halides are precipitated by silver nitrate; they can be further identified by color.
-Sulfates can be precipitated by barium chloride.
-Nitrates can be reduced to ammonia
Detecting Anions
is now used only as a pedagogical tool.
Qualitative inorganic analysis
are able to quickly detect the presence and concentrations of elements using a very small amount of sample.
Modern techniques such as atomic absorption spectroscopy and ICP-MS
