Gravimetric Analysis Flashcards
Determination of water amount in sample done through using a pre weighed absorbent trap.
Direct Analysis
Encompasses all techniques in which we measure mass or a change in mass.
Gravimetry
Commonly referred to as filter paper, range in pore size from 30µm to 2–3µm.
Cellulose Fiber Filters
Constructed from chemically inert borosilicate glass, range in pore size from 2.5 µm to 0.3 µm.
Glass Fiber Filters
Are made from a variety of materials, including cellulose nitrate and PTFE, are available with pore sizes from 5.0 µm to 0.1 µm.
Membrane Fiber Filters
Determination of water amount in sample done through using a pre weighed absorbent trap
Direct Analysis /Determination
An easier approach is to weigh the sample of food before and after heating, using the change in its mass as an indication of the amount of water originally present.
Indirect Analysis / Determination
A gravimetric method in which the signal is the mass of a precipitate. (analyzing ores)
Precipitation Gravimetry
Insoluble solid from liquid solution in gravimetry
Precipitate
A gravimetric method in which the signal is the mass of an electrode deposit on the cathode or anode in an electrochemical cell
Electrogravimetry
A process that assembles solid materials from molecules, ions or complexes in a solution.
Electrodeposition
A gravimetric method in which the loss of a volatile species gives rise to the signal.
Volatilization Gravimetry
A form of volatilization gravimetry in which the change in a sample’s mass
is monitored while it is heated.
Thermogravimetry
A gravimetric method in which the mass of a
particulate analyte is determined following its separation from its matrix.
Particulate Gravimetry
Are form of minute separate particles examples nitrates, sulfates and organic chemicals
Particulate
To achieve an accuracy of ±0.1% using an analytical balance with a sensitivity of ±0.1 mg, the precipitate must weigh at least 100 mg.
Scale of Operation
Non-optically active member of a set of stereoisomers
Meso - compound
Relative errors of 0.1–0.2% are routinely achieved.
Macro-major samples
It determine the components of an unknown material, to confirm the identity of a suspect material and to identify differences between similar materials.
Compositional Analysis
• The main purpose are for identifying, quantifying and purifying the individual components of the mixture.
• It is a liquid chromatography used to separate compounds that are dissolved in solutions
High Pressure Liquid Chromatography
• An analytical technique used to separate and detect the chemical components of a
sample mixture to determine their presence or absence and/or quantities.
• These chemical components are usually organic molecules or gases
Gas Chromatography
A process where a sample of some material (e.g., soil, waste or drinking water, bodily fluids, minerals, chemical
compounds) is analyzed for its
elemental and sometimes isotopic composition.
Elemental Analysis
• Instrument designed to measure various substances and other characteristics in a number of biological samples quickly, with minimal human assistance.
• These measured properties of blood and other fluids may be useful in the diagnosis of disease.
Automated Analysis
• A medical laboratory equipment used extensively in clinical laboratories.
• It is designed to conduct tests to measure chemicals at various stages of the biological processes on a wide range of test samples from blood, plasma, serum, and cerebrospinal fluid to urine.
Biochemistry analyzers
