Organic

how does the carbon-halogen bond enthalpy influence the rate of reaction?

weaker bond enthalpy = faster rate of reaction

catalytic cracking products

aromatic hydrocarbons and motor fuels

thermal cracking products

lots of alkenes

conditions for elimination

hot and dissolved in ethanol

why do major products form the most?

a tertiary carbocation has more alkyl groups that stabilise the carbocation with a positive inductive effect, so they tend to form in larger quantities

PVC uses

usually used for drain pipes. if plasticisers are added they keep the hydrocarbon chains further apart weakening the van der waals between chains making the molecule more flexible so they slide easily over each other

test for unsaturation

shake with bromine water, brown → colourless

why are addition polymers unreactive?

strong C-H and C-C bonds, is non-polar

K2Cr2O7 + 1°/ 2°/ 3°

• 1° orange → green aldehyde R−CH=O group. excess dichromate + heat under reflux → carboxylic acid

• 2° orange → green ketone C=O group

• 3° no change

Tollen’s test

1° + K2Cr2O7 → aldehyde

aldehyde + Tollen’s colourless → silver mirror

Fehling’s test

1° + K2CrO7 → aldehyde

aldehyde + Fehling’s blue → brick red

ethene → ethanol catalyst?

hot phosphoric acid + steam

are alcohols soluble?

shorter chain alcohols are because the H bonding dominates, longer chain alcohols aren’t because the non-polar chain dominates

more vibrations → ?

more IR absorbed → warmer earth (more is remitted)

nucleophilic substitution conditions

warm, aqueous, (excess ammonia)