Standard Calibration Flashcards
Method of identifying a chemical species
Qualitative Analysis
Method to determine the amount of a constituent.
Quantitative Analysis
Quantitative methods can be classified as gravimetric, volumetric, or instrumental.
Used for samples with masses > 0.1 g.
Macro Analysis
Used for samples with masses of 0.01 to 0.1 g.
Semimicro Analysis
Used for samples with masses of 10^-4 to 10^-2 g.
Micro Analysis
used for samples with masses of < 10^-4
Ultramicro Analysis
Present in the range of 1 to 100% by mass.
Major constituents
Present in the range of 0.01 to 1% by mass.
Minor constituents
Present in the range of 100 ppm (0.01%) and 1 ppb.
Trace constituents
Present in amounts lower than 1 ppb.
Ultratrace constituents
Occur when extraneous species in the matrix interfere with determination of the analyte.
Matrix effects
Samples are analyzed, but constituents or concentrations are determined.
Acquiring a representative fraction of the material of interest. It is often the most difficult aspect of an analysis.
Sampling
Items chosen for analysis.
Sampling units or sampling increments
The collecting of sampling units or increments. A miniature replica of the entire mass of material to be analyzed
Gross sample
The gross sample is usually reduced in size and homogenized to create the laboratory sample for analysis.
Two goals of the sampling process.
To obtain a mean analyte concentration that is an unbiased estimate of the population mean.
To obtain a variance in the measured analyte concentration that is an unbiased estimate of population variance.
A state intermediate between a suspension and a solution.
Colloid
Mimics the steps in a determination that would be taken by a human analyst.
Batch or discrete approach
Involve inserting the sample into a flowing stream where several operations can be performed before the sample passes through a flow-through detector.
Continuous flow methods
Divide a sample into discrete samples separated by gas bubbles that confine the sample and minimize cross-contamination.
Segmented-flow analyzers