Organic Chemistry Flashcards
What is the general formula for an alcohol?
CnH2n+1OH
What happens to the boiling point of an alcohol as the chain length increases?
The boiling point increases
Why does the boiling point of an alcohol increase as the chain length increases?
- There is a greater surface area
- Therefore a stronger induced dipole
What happens to the solubility of an alcohol as the chain length increases?
The solubility decreases
How can alcohols be used as fuels?
They can be combusted
What is used to oxidise primary/secondary alcohols?
Acidified potassium dichromate
What can primary alcohols be oxidised to?
- Aldehydes (distilled straight away)
- Carboxylic acids (heated under reflux)
How can we distinguish between primary and secondary alcohols?
Use Fehling’s solution, only primary alcohols will react
What can secondary alcohols be oxidised to?
Ketones
How can alcohols be dehydrated?
- Water molecule eliminated by using concentrated sulphuric acid/phosphoric acid
- Heated and passed over aluminium oxide
- Alkene formed
What is the general formula for an alkane?
CnH2n+2
What are the two factors that affect the boiling point of an alkane?
- Chain length
- Branching
How is the boiling point of an alkane affected by chain length?
- Longer chain = greater surface area
- Larger dipole-dipole forces
How is the boiling point of an alkane affected by branching?
- More branching = lower boiling point
- Smaller surface area
- Fewer dipole-dipole forces
What are the three steps of radical substitution?
- Initiation
- Propagation
- Termination
What are the two types of bonds that alkenes can have?
- Pi bonds: overlap of p-orbitals above and below carbon atoms
- Sigma bonds: direct overlap of electron clouds
What is Markownikoff’s rule?
Hydrogen attaches to the carbon with the most hydrogens attached to it
What is fission?
The breaking of covalent bonds
What is bond formation?
Bond formation is when two oppositely charged ions/radicals collide
How can diols be formed?
Alkene + potassium manganate (VIII)
What are free radicals?
Very reactive species with an unpaired electron
What are halogenoalkanes?
- Saturated organic compounds
- Contain carbon and at least one halogen atom
What are nucleophiles?
- Electron pair donors
- Will attack electron poor areas
- Usually has some type of negative charge
Why is radical substitution limited in its use of the production of halogenoalkanes?
- Further substitution reactions may occur
- Mixture of wanted and unwanted products form
- Have to undergo further separation processes
What is reformation?
Reformation is the process of converting straight chain alkanes to branched chain or cyclic alkanes using a platinum catalyst.
