Module 6: Organic Chemistry and Analysis Flashcards
What are the reagents needed for the nitration of benzene?
– HNO3
– Concentrated H2SO4 under relux
What conditions must the nitration of benzene be carried out on?
– Under reflux
– 50-60 degrees celcius
Explain why the reaction of phenol is more reactive with bromine in comparison to benzene and it doen’t need an halogen carrier.
– Phenol has a lone pair of electrons on the oxygen in the p orbital which is also deocalised into the πsystem
– Hence phenol has high electron density so its capable of polarising bonds
– So it is more susceptible to an electrophillic attack
– Benzene ring is activated
State the general uses for phenols
– Disinfectants
– Antiseptics
– Detergents
What is an electrophile?
An electrophile is an elctron pair donor
What is a nucleophile?
An elctron pair acceptor
What is a stereoisomer>
Stereoisomers have the same structural formula but the atoms are arranged differently in space.
What is the test for aldehydes?
– Tollen’s Reagent.
– When heated, the aldehyde is oxidised and the silver ions are reduced to silver causing a silver mirror to form
In terms of orbital overlap, what are the similarities and differences between the bonding in the kekule model and the delocalised model of benzene?
SIMILARITIES
– Orbitals overlap sideways.
– Pi-bond is above and below the ring.
DIFFERENCES
– Kekule has alternating 3 pi-bonds.
Experimental evidence led to the general acceptance of the delocalised model over the kekule kodel.
What are the pieces of evidence to support the delocalised model of benzene?
BOND LENGTH:
– (C–C) bond length is between single (C–C) and double bond (C=C) OR all (C–C) bond lengths are the same
ΔH HYDROGENATION:
– ∆H hydrogenation less (exothermic) than expected.
Resistance to reaction:
– Benzene is less reactive than alkenes OR bromination of benzene requires a catalyst/halogen carrier OR benzene does not react with/decolourise bromine (at room temperature) OR benzene reacts by substitution OR benzene does not (readily) react by addition
What are the two types of polymerisation?
– Addition Polymerisation
– Condensation Polymerisation
Nitrobenzene ———–> aminobenzene/phenylamine?
Name of reaction?
– Reagent: Sn, HCl
– Condition: Under reflux, Neutralise
– Reduction reaction
What are the reagents and conditions of the oxidation of a primary alcohol to a carboxylic acid?
Reagents: Acidified Potassium dichromate
Condition: Under reflux because if you distil it, you will form an aldehyde.
What is the reagent for making an acyl chloride?
– SOCl2
What is a homologous series?
Homologous series is a series of organic compounds with the same functional group
