Paper 2 ehaiblv Flashcards
What are the conditions for NaBH4 usage?
Aqueous ethanol
Why are ketones less reactive than aldehydes?
The havea bigger inductive effect from adjacent alkyl groups and so this reduces the d+ on the C bond.
What is used as a catalyst for the reaction of an alcohol and a carboxylic acid to produce an ester.
Concentrated H2SO4.
What are 4 uses of esters?
Solvents, plasticisers, perfumes and food colouring.
What solution does acid or base hydrolysis of esters occur in?
Aqueous solution.
What is biodiesel made of?
Methyl esters and long chain carboxylic acids.
How is biodiesel made?
Reacting triglycerides with methanol in the presence of an alkali catalyst such as NaOH.
What does the gradient represent on a graph of log(rate) against log(Y)?
The order of the reactant.
What does the y-intercept reresent on a graph os log(rate) against log(Y)?
Log(K)
What can be calculated from the gradient of a graph of 1/T against ln(rate)?
The activation energy. (x 8.31)
What are the conditions for oxidation of aldehydes or ketones with K2Cr2O7?
heat under reflux
Give two ways carbonyls can be reduced?
NaBH4 in aqueous ethanol or H2 and a Ni catalyst.
What are the reactants and conditions for the formation of hydroxynitriles from carbonyls?
NaCN and dilute sulfuric acid.
What does the nucleophilic addition of CN- to a carbonyl produce?
A racemic mixture of hydroxynitrililes
What are carboxylic acids strong enough to do?
Displace CO2 from carbonates.
Why is dissociation of carboxylic acids likely?
The salts are stabilised by delocalisation.
Why can methanoic acid be oxidised?
It has effectively an aldehyde group.
What is needed for a carboxylic acid to react with an alcohol and what is produced?
An ester and water, requires a strong acid catalyst.
What are the conditions for hydrolysis of an ester?
Dilute acid, heat under reflux.
Does the reaction of an ester with a dilute acid or dilute NaOH co to completion?
NaOH, reaction is not reversible.
What are soaps?
long chain carboxylic acids, produced by the hydrolysis of fats.
What is aspirin made from?
2-hydroxybenzoic acid.
Why may there be a loss of yield when making aspirin by recrystallisation?
-crystals lost in filtration or washing, some product stays in solution after recrystallisation or other side reactions occur.
What is the H-C-C bond angle in benzene?
120
When is the name phenyl- used?
When benzene ring is regarded as a substituent side group.
Why si the nitration of benzene important
Explosives manufacture and formation of amines for use in dyes.
Whata re the conditions of the friedel crafts acylation?
Heat under reflux with acyl chloride in the presence of anydrous aluminium chloride catalyst.
Why are friedel-crafts reacyions important?
Introduces a reactive group onto the benzene ring.
What is LiAlH4 used for?
Reduction, reducing agent. W
What is required for dehydration of alcohols?
H2SO4
What do amines as bases react with acids to produce?
Ammonium salts.
Addition of what to an ammonium salt will convert it back to the amine?
NaOH
Gve two ways amines cane be prodced from nitriles.
Nucleophiliic substitution with a haloalkane.
Convert haloalkane to nitrile with KCN in ethanol (heating under reflux). REduce the nitrile using LiAl4 in ether.
What is TLC?
Plat is coated with a solid and solvent moves up the plate.
What is CC?
A column is packed with a solid and a solvent moves down the column.
What is GC?
A column is packed with a solid or solid coated by a liquid, has is passed through the column under high pressure and temp.
What must the gas be in in GC?
Inert eg H2 or N
What is GC used for?
Seperating volatile liquids.
Why would mass spec not work on isomers?
They have the same M/z value.
What is reflux?
The continuous evaporation and condensation of a mixture of liquids heated to the boiling point for a long period of time.
What is the bond angle in cyclohexane?
109
Why do different amino acids have different Rf values?
Different polarities distance moves is specific to the polarity.
What is required for the nucleophilic substitution of bromoethane to produce ethanamine?
Ethanolic solvent.
Why can primary amines react to form quarternary ammonium salts?
Each organic product is a stronger nucleophile than the reagent that made it,
What is the stationary phase and what is the developing agent for TLC/
SiO2 and ninhydrin or UV light.
Name 4 solvents used in NMR.
D2O, CCl4, CDCl3, C6D6.
What is the bonding between polymer chains?
Van der Waals.
How can u convert nitrobenzene to aminobenzene?
Add HCl and Sn under reflux then add NaOH at room temp.
