⚛ Atomic Absorption Spectroscopy (AAS)

Spectroscopy

The interaction between radiation and matter.

Excited State

A higher energy orbit in an atom where electrons can transition after absorbing energy.

Ground State

The original energy orbit of an electron before it gets excited.

Atomic Absorption Spectroscopy (AAS)

A quantitative technique used to analyze the concentration of metal ions in a sample using spectroscopy.

Beer-Lambert Law

States that the absorption of electromagnetic radiation (EMR) is directly proportional to the concentration of metal ions or atoms in a sample.

Hollow Cathode Lamp

The lamp that produces EMR needed to excite electrons in the metal atom, made from the same metal being analyzed.

Monochromator

Receives EMR with the characteristic wavelength of the analyzed metal while eliminating other sources of light.

Detector

Measures the intensity of radiation after it has passed through the monochromator.

Calibration Curve

A graph used to find the concentration of an unknown sample by plotting absorbance against concentration of standard solutions.

ppm (parts per million)

A unit of measurement indicating 1 milligram of metal per liter of solvent.

Characteristic Wavelength

The specific wavelength of EMR that a particular metal can absorb.

Trace Amounts

Very small quantities of metal ions that can be detected and measured by AAS.

Extinction Coefficient (ε)

A measure of how strongly a chemical species absorbs light at a given wavelength.

Absorbance (A)

The measure of the amount of light absorbed by a sample, calculated using the ratio of intensities of light.