Chemical Analysis and Instrumental Methods

sian.allison
Mind Map by , created over 5 years ago

GCSE Science (Chemistry Additional) Mind Map on Chemical Analysis and Instrumental Methods, created by sian.allison on 01/24/2014.

104
1
0
Tags
sian.allison
Created by sian.allison over 5 years ago
Biology- Genes and Variation
Laura Perry
AQA Physics P1 Quiz
Bella Statham
GCSE Combined Science
Derek Cumberbatch
Social Psychology, Milgram (1963)
Robyn Chamberlain
Plant Anatomy Quiz
Kit Sinclair
Biology B1.1 - Genes
raffia.khalid99
Edexcel Biology chapter 1
Anna Bowring
Flame tests
Joshua Rees
Testing for ions
Joshua Rees
The Flowering Plant and Photosynthesis
lalalucy13
Chemical Analysis and Instrumental Methods
1 Artificial Colours can be seperated using paper chromatography
1.1 A food colouring might contain one dye or it might be a mixture of dyes
1.2 1. Extract the colour from a food sample by placing it in a small cup with a few drops of slovent (water, ethonal etc)
1.2.1 2. Put spots of the coloured solution on a pencil baseline on filter paper
1.2.1.1 3. Roll up the sheet and put it in a beaker with some solvent - but keep the baseline above the level of solvent
1.2.1.1.1 4. The solvent seeps up the paper taking the dyes with it. Different dyes form spots in different places
1.2.1.1.1.1 5. Watch out though a chromatogram with four spots means at least four dyes not exactly four dyes. There could be five dyes with two of them making a spot in the same place
2 Machines can also analyse unknown substances
2.1 You can identify elements and compounds using instrumental methods
2.1.1 Advantages
2.1.1.1 Very sensitive can detect even the tiniest amount of substance
2.1.1.2 Very fast and tests can be automated
2.1.1.3 Very accurate
3 Gas chromatography
3.1 Seperate out a mixture of compounds to help identify the substances
3.2 1 .A gas is used to carry substances through a column packed with a solid material
3.2.1 2. The substances travel through the tube at different speeds so they are seperated.
3.2.1.1 3. The time they take to reach the detector is called retention time. It helps identify substances
3.2.1.1.1 4. The recorder draws a gas chromatograph. The number of peaks shows the number of different compounds in the sample
3.2.1.1.1.1 5. The position of the peaks shows the retention time of each substance
3.2.1.1.1.1.1 6. The gas chromatography column can also be linked to a mass spectrometer. This process is known as GC-MS and can identify the substances leaving the column very accurately
3.2.1.1.1.1.1.1 7. You can work out the relative molecular mass of each substance from the graph it draws. You just read off from the molecular ion peak