Introduction to Analytical Chemistry

Study Notes

Analytical Chemistry is the science and technology used to determine the chemical composition of samples.
Qualitative analysis determines what is in the sample.
Quantitative analysis determines how much of something is in the sample.

Clinical analytical chemistry is used to test blood and other bodily fluids.
Forensic analytical chemistry is used by agencies like the CSI.
Environmental analytical chemistry studies samples like rocks, soil, sediment, water, air, and biota.
Food analytical chemistry determines what is in food and how much of it is there.
Quality control analytical chemistry checks on manufacturing processes.
Scientific research analytical chemistry supports fields like geology, anthropology, and the exploration of planets.

A population refers to the entirety of the substance being analyzed.
A sample is a representative subset of the population.
A sampling unit or sampling increment refers to individual samples taken from the population.
A gross sample is the collection of individual samples.
A representative sample accurately reflects the composition of the population at the time of collection.

Analytical results need to be specific.
Questions about a sample should consider factors like location, depth, time of collection, and whether dissolved or total components are being measured.

Environmental water samples may contain undissolved particles like silt, sand, or algae.
Metals in water can be dissolved or attached to solid particles suspended in the water.
Total metal includes both dissolved and undissolved metal.
Dissolved metal is measured in the filtrate after filtering out solid particles.
Total metal is measured in the digestate after digesting the sample to dissolve undissolved metal.