C8-Chemical Analysis KW Flashcards
Chromatogram
A graph that shows the result of separating the components of a mixture by chromatography
Chromatography
A technique used to separate mixtures due to the distribution of the substances between the stationary and mobile phase. It can give information to help identify substances
Flame emission spectroscopy
An instrumental method used to analyse metal ions in solutions
Formulation
A mixture that has been designed as a useful product. They are made by mixing the components in carefully measured quantities to ensure that the product has the required properties
Flame test
Qualitative test used to identify metal ions (cations). Carried out by inserting a nichrome wire loop with the unknown compound on into a flame and observing the colour
Impure substance
A substance made up of two or more elements or compounds that are not bonded together chemically
Instrumental methods
Instrumental methods can be used to detect and identify elements and compounds. They are accurate, sensitive and rapid
Litmus paper
Paper stained with litmus which can be used to indicate the acidity or alkalinity of a substance. Used in the test for chlorine
Mobile phase
Where the molecules can move during chromatography. It is always a liquid or gas
Precipitation
The creation of a solid from a solution
Pure substance
In chemistry a pure substance is a single element or compound, not mixed with any other substance. In everyday language, a pure substance can mean a substance that has had nothing added to it, so it is unadulterated and in its natural state.
Rf value
The ratio of the distance moved by a compound to the distance moved by the solvent.
Stationary phase
Where the molecules are stationary during chromatography. It is a solid or a liquid supported on a solid
