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 →

Lesson 10 – Intermolecular Forces

Intermolecular forces act between molecules. They are a lot weaker than ionic and covalent bonds and are caused by small dipoles in different molecules. There are three types of intermolecular force: Hydrogen Bond Permanent Dipole-Dipole Forces Van der Waals’ Forces Permanent Dipole-Dipole Interactions The permanent dipole of one polar molecule attracts the permanent dipole of … Continue reading →

Lesson 9 – Covalent Bonds

Covalent donds happen between two non-metals. In convalent bonds a pair of electrons is shared between two atoms.The negatively charged electrons attract the positively charged electrons. A covalent bond is directional and acts only between the two atoms involved. Intermolecular bonds are very weak. Dative Covalent Bonds In dative covalent bonds only one of the … Continue reading →