DF6 Flashcards
What is the physical state of alkenes?
Ethene, propene and butene are gases, after that they are liquids and eventually solids.
What is an electrophile?
A positive ion, or a molecule with a partial positive charge, that will be attracted to a negatively charged region and react by accepting a lone pair of electrons to form a covalent bond.
What is σ/Σ?
Greek letter sigma (equivalent to an s).
What is a σ-bond?
In a single bond, the two electrons are arranged between the atoms in an area of increased electron density.
What is π?
Greek letter pi (equivalent to a p).
What is a π-bond?
Consists of two areas of negative charge - one above and the other below the line of atoms.
How do you test for unsaturation in an organic compound?
- Add bromine water to an alkene
- Red/brown bromine becomes decolourised
What is carbocation?
An ion with a positively-charged carbon atom.
What is the rate of reaction of carbocations?
React very rapidly with anything that has electrons to share.
What does a reaction mechanism show?
Represents the sequence of events in a reaction using the movement of electrons (shown by curly arrows).
What is an addition reaction?
A reaction where two or more molecules react to form a single larger molecule.
What is electrophilic addition?
An addition reaction where the initial attack is by an electrophile.
Do alkenes react with hydrogen bromide?
Yes but ions are not involved - mechanism involves a radical addition.
What is an example of a hydration reaction?
Addition of water to an alkene.
