Organic Analysis Flashcards
How are primary and secondary alcohols identified?
Acidified potassium dichromate
What would be observed if acidified potassium dichromate was added to a primary or secondary alcohol?
It will turn from orange to green
What would be observed if acidified potassium dichromate was added to a tertiary alcohol?
It will remain orange
How can all alcohols be identified?
Metallic sodium
What would be observed if metallic sodium was added to an alcohol?
Hydrogen gas would be formed (identified by the squeaky pop test)
How are aldehydes identified?
Tollens’ reagent and Fehling’s solution
What would be observed if Tollens’ reagent was added to an aldehyde?
A silver mirror forms from a colourless solution
What would be observed if Fehling’s solution was added to an aldehyde?
Brick red precipitate forms from blue solution
How are alkenes identified?
Bromine water
What would be observed if bromine water was added to an alkene?
It would turn from orange to colourless
How are carboxylic acids identified?
Solid sodium carbonate
What would be observed if solid sodium carbonate was added to a carboxylic acid?
White solid disappears and effervescence
How are halogenoalkane’s identified?
Sodium hydroxide and sliver nitrate
What would be observed if sodium hydroxide and silver nitrate were added to a halogenoalkane?
A silver halide precipitate would form (white, cream or yellow)
What can mass spectrometry be used for in terms of organic chemistry?
Determining the molecular formula of a compound
What is high resolution mass spectrometry?
A more sensitive form of mass spectrometry
What does high resolution mass spectrometry allow us to do?
Determine the Mr of a substance to several decimal places
What do covalent bonds do continuously?
Vibrate
What determines the frequency at which a covalent bond vibrates at?
The unique atom combination and type (single/double/triple) of the bond
What region of the electromagnetic spectrum do covalent bonds vibrate in?
The infrared region
What radiation does a covalent bond absorb?
Radiation that has the same frequency as the natural frequency of the bond
What is the fingerprint region?
The area of an infrared spectrum below 1500
How can the fingerprint region be used to identify a molecule?
The fingerprint region is unique to each molecule and can be compared to a database of IR spectra of known molecules
How is the absorption of infrared radiation linked to global warming?
The greenhouse gases carbon dioxide, methane and water vapour cause the greenhouse effect because they are very efficient at absorbing infrared radiation
