Alkanes

METHANE

ETHANE

PROPANE

BUTANE

PENTANE

3.4 I can recall the products of the complete and incomplete combustion of alkanes

   Saturated hydrocarbons are called alkanes

·         Small chain alkanes are used as fuels

3.       The reaction is called combustion

4.       The word equation for  this chemical reaction is :

fuel (methane) + oxygen → carbon dioxide + water + ENERGY (heat, light, sound)

5.       If there is insufficient oxygen then the word equation is:

fuel (methane) + oxygen → carbon monoxide + water + ENERGY (heat, light, sound)

6.       The problem with this reaction is that carbon monoxide is produced this gas is a poisonous gas to the human body (see objective 5.11)

7.       Where can you find incomplete combustion? In cars

8.       What is used to reduce the harmful products from incomplete combustion? 

9.       During incomplete combustion a smoky flame is often seen, explain this observation

10.   Describe the two chemical tests for water   blue anhydrous cobalt chloride turns pink

11.   Describe the chemical test for carbon dioxide gas lime water turns milky

12.   Describe a physical test for water- boiling point 100 Celsius

Extn: write a balanced equation (with state symbols) for the combustion of propane gas

3.1 I can explain the terms homologous series, hydrocarbon, saturated, unsaturated, general formula and isomerism

Term	Definition	Example
Homologous series	A family of compounds with the same general formula	alkanes
Hydrocarbon	a compound containing hydrogen and carbon	Methane
Saturated hydrocarbon	the fact that each carbon has maximum number of bonds	ethane, propane
Unsaturated hydrocarbon	hydrocarbons which have double or triple covalent bonds.	butane
General formula	A mathematical formula to show how many carbons and hydrogens there are in the homologous series.	CnH2n+2
Isomerism