Analysing Organic Compounds

Question 1

How to analyse chromatogram

Answer 1

Calculate Rf value

Compare Rf values to known compounds

Question 2

Why will similar compounds be difficult to analyse w/TLC

Answer 2

Won’t separate ∵ have similar Rf values

Question 3

How would you use gas chromatography + mass spec to analyse a compound

Answer 3

Gas chromatograph = separates molecules within compound
Mass spec = produces distinctive fragmentation patterns
Identification via computer using spectral database

Question 4

Rf value

Answer 4

Distance moved by solute/compound ÷ distance moved by solvent

Question 5

Retention time

Answer 5

Time between injection and emergence of a component

Question 6

TLC

Answer 6

Used to separate + identify dissolved substances

Question 7

Describe you spell NMR spec in medicine

Answer 7

Magnetic resonance imaging (MRI)

Question 8

Suggest 2 benefits of using single stereoisomers in the synthesis of drugs

Answer 8

• fewer side effects
• increases effectiveness
• stops the need in separating stereoisomers = saves money

Question 9

How does GC separate compounds in the mixture?

Answer 9

Relative Solubility in stationary phase

Question 10

2 methods to obtain 1optical isomer

Answer 10

• use enzymes/bacteria

* use chiral catalysts