Chemistry - Unit 1

Final exam

GC/MS

Gas Chromatography/Mass Spectrometry separates mixtures to see their individual components and using mass spectrum and spectrometry we can identify them based on their mass-to-charge ratio.

Both quantitative and qualitative information, confirmatory

Chromatography

Technique where a mixture is separated between the stationary and mobile phases.

The stationary is fixed and the mobile carries the mixture through the stationary phase (liquid or gas)

Information- Quantity and qualtity, Confirmatory

Limitation- Low resolution

Radioactive Decay

Method used for determining the age of an object containing organic material

Half-life

The amount of time it takes for half the radioactive isotopes to decay only depends on the identity of the radioisotope involved C14 HL-5730 years

Accelerator mass Spectrometry

Used in radiocarbon dating. Highly sensitive technique used to measure ratio of different isotopes in a sample.

How AMS works

Molecules are vaporized then ionized by electron beam bombarding vapor, positive ions created accelerate towards negative plates at a speed dependent mass, deflected by a magnetic field depending on mass finally reaching the detector

Infrared Spectroscopy

Technique that analyzes interactions of infrared light with matter to identify them, reaches detector where some light will be absorbed by sample and some will pass through to determine the structure of the molecule

Forensic applications to IR

Identification and verification of unknown compounds, fiber analysis, paint and ink analysis