Electrophilic Substitution The electrophile is attrated to the electron rich ring accepting a pair of π-electrons to create a covalent bond One of the Hydrogens is replaced by the -NO2 (nitro) group Conditions for reaction Temperature: 50oC Catalyst: H2SO4 Friedel-Crafts Acylation CH3COCl +C6H6—-> C6H5COCH3 Catalyst: AlCl3 Friedel-Crafts Alkylation CH3Cl +C6H6—-> C6H5CH3 Catalyst: AlCl3 Sulfonation H2SO4 … Continue reading
Author Archives: naomisbell
Benzene
Benzene – C6H6 Properties of Benzene Melting Point: 5.5°C Density: 876.50 kg/m³ Boiling point: 80.1 °C The discovery of Benzene Benzene was first isolated in 1825 by Michael Faraday from an oily film that deposited from the gas used for lighting. In 1833, it was the discovered again by Eilhard Mitscherlich who distilled it from … Continue reading
Lesson 18 – The Boltzman Distribution
For a reaction to take place, 3 things must occur: There must be a collision Both particles must have enough energy The particles must have the correct orientation To increase or speed up the reaction you can: Increase pressure/concentration Increase temperature Increase surface area Add a catalyst The purple line shows what happens when you increase the … Continue reading
Lesson 17 – Reactions of Alcohols
There are three types of alcohol: Primary, Secondary and Tertiary Primary (at the end of a chain): When oxidized under distillation they form Aldehydes When oxidized under reflux they form Carboxylic Acid Secondary (middle of chain): When oxidized under reflux they form Ketones Tertiary: Tertiary alcohols do not oxidize Continue reading
Lesson 16 – Reactions of Alkenes
Alkenes undergo Addition Reactions. There are three different types of addition reaction: Hydrogenation, Halogenation and Hydration. Hydrogenation: Halogenation: Hydration: Continue reading
Lesson 15 – Reactions of Alkanes
A substitution reaction of alkanes has three stages: Initiation, Propagation, Termination 1. Initiation: 2. Propagation: 3. Termination: Continue reading
Lesson 14 – Organic Reagents
Homolytic Fission – is the breaking of a covalent bond, with one of the bonded electrons going to each atom, forming two radicals Radical – a species with an unpaired electron (a single dot is often written next to the species to represent the unpaired electron) Heterolytic Fission – is the breaking of a covalent … Continue reading
Lesson 13 – Naming Alkanes/Alkenes
Alkanes – The homologous series with the general formula CnH2n+2 How to Name Alkanes 1. Find the longest Carbon Chain 2. Decide which functional group is present 3. Deduce any side chains REMEMBER: 1. Number from the end so the sum of substituent groups is the smallest 2. Chains can ‘go round the corner’ to … Continue reading
Lesson 12 – Periodicity
Periodicity: the regular periodic variation of properties of elements with atomic number and position in the Periodic Table Variation in first ionisation energies and atomic radii: First ionisation energy generally increases across the periodic table – Because the nuclear charge is increased so the radius become smaller as the electrons are being pulled toward the … Continue reading
Lesson 11 – The Periodic Table
In ancient Greece, around 384-322 BC, philosophers such as Aristotle theorised that everything was composed of just four elements: Earth, Water, Air and Fire. However we now realise that these are just states of matter: solid, liquid and gas. Antoine-Laurent de Lavoisier In 1798, Antoine-Laurent de Lavoisier and his wife together produced what is now considered … Continue reading