Organic points I dont know as well

Why do carboxylic acids dissolve in water?

• they can form hydrogen bonds with water molecules

• hydrogen bonding between lone pair on O of one molecule and d+ H on the other

What is some evidence of the delocalised model of benzene (instead of Kekule’s model)?

1. Enthalpy of hydrogenation

• kekule model —> -360 kJmol-1

• actual benzene —> -208 kJmol-1

• benzene is more stable than the theoretical model

• the delocalised rings make it more stable

2. Benzene doesn’t turn bromine water colourless

• if benzene contained C=C bonds, it would turn bromine colourless as would have a positive test for unsaturation

• so benzene can’t be the Kekule model as this contains C=C bonds

3. The carbon-carbon bonds are the same length

• if had kekule structure, would contain C-C bonds and C=C bonds, so would have bonds of different lengths

When is Sn/conc HCl used? Under reflux with excess NaOH

To reduce (add Hs) aromatic nitro compounds into aromatic amines

When is H2/Ni used?

To reduce (add Hs) alkenes to alkanes, or nitriles to aliphatic amines (no benzene rings)

Reagents and conditions for alcohol —> carboxylic acid?

(Alcohol will be primary or secondary)

Reflux, acidified potassium dichromate

Reagents and conditions for alkene —> alcohol?

When might alkene —> alcohol be used?

• Steam, high temperature and pressure, phosphoric acid catalyst

• Hydration of alkenes to form alcohols (instead of forming alcohols by fermentation)

What is a homologous series?

• series of compounds with the same functional group

• and similar chemical properties

What would be a suitable reagent for hydrolysis of a protein?

conc. HCl

Use of aromatic amines?

Manufacture of dyes

Use of quaternary ammonium salts?

Cationic surfactants

Use of ester hydrolysis under alkaline conditions?

Making soaps

Use of vegetable oils + methanol?

Biodiesel

What is friedel crafts acylation?

What is the catalyst?

What is the reactive intermediate (electrophile)?

• Benzene reacting with an acyl chloride

• AlCl3 catalyst

• R-CO+ electrophile (ie the Cl has been removed from the acyl chloride to form positive intermediate)

The AlCl3 catalyst is used to form the positive intermediate from the acyl chloride that reacts with benzene:

R-COCl + AlCl3 —> R-CO+ + AlCl4

What is the nitrogen containing electrophile that reacts with benzene? And how is it formed?

• NO2 +

• Formed from conc. H2SO4 and conc. HNO3

H2SO4 + HNO3 —> H2NO3+ + HSO4 -

H2NO3+ —> H2O + NO2+

H2SO4 + HNO3 —> HSO4- + NO2+ + H2O as a simplified single equation

Reagent and conditions for reducing aldehydes and ketones?

NaBH4 in aqueous solution with methanol

Reduction of aldehydes and ketones = …?

Alcohols (primary for aldehyde, secondary for ketone)

Catalytic cracking conditions and catalyst?

What does it produce?

• slight pressure

• zeolite catalyst

Produces motor fuel and aromatic hydrocarbons

Catalyst for catalytic converters?

Rhodium

For electrophilic addition mechanism with H2SO4, how should you draw the H2SO4?

H - OSO3H

(So that you can show the d+ H and d- O)

Equations for depletion of ozone?

How do CFCs cause depletion of ozone?

• O3 + Cl. —> ClO. + O2

• ClO. + O3 —> 2O2 + Cl.

C-Cl bonds in CFCs are broken by UV light to form chlorine radicals

Why does EZ isomerism occur?

Due to restricted rotation around the planar carbon-carbon double bond

Equations that show ethanol produced by fermentation is carbon neutral fuel (and state why it still is not carbon neutral)

Photosynthesis in the plants being used:

6CO2 + 6H2O —> C6H12O6 + 6O2

Fermentation:

C6H12O6 —> 2CH3CH2OH (ethanol) + 2CO2

Combustion of ethanol as biofuel:

2CH3CH2OH + 6O2 —> 4CO2 + 6H2O

6CO2 used, 6CO2 made = carbon neutral

BUT, transport of ethanol means it isn’t actually carbon neutral

What is the nucleophile in nucleophilic addition mechanisms for reduction reactions with NaBH4?

H- (with a electron pair and negative charge)

Common uses of esters?

Food flavourings, perfumes

(Because esters are sweet smelling)

Why do substitution reacts occur in preference to addition reactions in benzene compounds?

• addition reactions involve breaking of the benzene ring

• The benzene ring is very stable and requires lots of energy to break

• The delocalised ring has a high electron density, leading to electrophilic attack and substitution

Polymers teryline, nylon and Kevlar

• Terylene - ester polymer

• Nylon - amide polymer

• Kevlar - amide polymer

How does cisplatin prevent DNA replication in cancer cells?

By a ligand replacement reaction with DNA in which a bond is formed between platinum and a nitrogen atom on guanine

Positives and negatives of cisplatin

+
Prevents replication of cancer cells

-

Hair loss

Drug has to be administered in small amounts to try to reduce effects on healthy cells

What type of solvent must the sample be dissolved in in H NMR spectra?

Deuterated solvents or CCl4

(Can’t have H^1 in it)