Distillation and Cracking 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Calderglen High School
What is FRACTIONAL DISTILLATION? 1 What is FRACTIONAL DISTILLATION? answer The process in which a mixture of substances (eg crude oil) is heated and separates according to the boiling points of the substances. Calderglen High School
Calderglen High School 2 What is a FRACTION? answer A group of hydrocarbon compounds with boiling points within a given range. Calderglen High School
What is the BOILING POINT of a liquid? 3 What is the BOILING POINT of a liquid? answer The temperature at which a substance changes from a liquid to a gas. Calderglen High School
Calderglen High School What is FLAMMABILITY? 4 answer Flammability is a measure of how easily a fuel ignites and how well it burns. The flammability of crude oil fractions decreases as their chain length increases. Calderglen High School
5 What is VISCOSITY? answer Viscosity is a measure of the thickness of a liquid. The viscosity of crude oil fractions increases as their chain length increases. Calderglen High School
Calderglen High School 6 Name the typical fractions obtained from crude oil and their chain length answer Refinery Gases : 1 to 4 Gasoline (Naphtha): 5 to 12 Kerosine (Paraffin): 10 to 16 Gas Oil: 12 to 25 Residue: 25+ Calderglen High School
Give some uses of the typical fractions obtained from crude oil 7 Give some uses of the typical fractions obtained from crude oil answer Petroleum Gas : Bottled Gases Gasoline: Petrol, Chemical Production Kerosine: Aviation Fuel Gas Oil: Diesel, Central Heating Fuel, Lubricating Oils Residue : Bitumen for roads and roofs mmcl2003
There are not enough of the useful short chain fractions 8 When CRUDE OIL is distilled what is the problem concerning the amounts of fractions obtained? answer There are not enough of the useful short chain fractions It is mainly the long chain hydrocarbons that are obtained Calderglen High School
Boiling point increases as the number of carbons increases 9 What is the connection between the boiling point of alkanes and their number of carbons? answer Boiling point increases as the number of carbons increases Calderglen High School
Give examples of uses for ALKANES 10 Give examples of uses for ALKANES answer Methane – natural gas Propane – bottled gas Octane – petrol Calderglen High School
What do alkanes, alkenes and cycloalkanes have in common ? 11 What do alkanes, alkenes and cycloalkanes have in common ? answer They are all hydrocarbons so burn in a plentiful supply of air to produce carbon dioxide and water Calderglen High School
What is catalytic cracking? 12 What is catalytic cracking? answer A process for breaking long chain molecules into smaller more useful molecules Calderglen High School
Small unsaturated molecules are used to make plastics 13 What is the main use for the small unsaturated molecules (eg ethene) obtained by the cracking of long chain hydrocarbons? answer Small unsaturated molecules are used to make plastics Calderglen High School
One will be saturated (C-C) One will be unsaturated (C=C) 14 Apart from the product molecules being smaller, what is different about one of the products obtained in cracking? answer One will be saturated (C-C) One will be unsaturated (C=C) Calderglen High School