Basic chemistry help for students and teachers

 

Interactive Chemistry Worksheets for Students

 

Periodic table

Naming compounds

Basic formula

Simple compounds

Ionic compounds 1

Ionic compounds 2

Chemical suffixes

Old chemical names

Hydrocarbons - Alkanes

Alkanes, alkenes & alkynes

Alkanols to alkanoic acids

 

Common compounds

Common formula quiz

Acids, bases and salts

Covalent compounds

Printable worksheets
 

 

Combustion is the burning of a fuel with the production of energy or heat

Examples of combustion reactions

1. Cellular respiration

Cellular respiration is the process whereby cells in our bodies obtain energy. Glucose reacts with oxygen producing carbon dioxide and water with the release of energy.

Glucose + oxygen carbon dioxide + water + energy

C6H12O6 + 6O2 6CO2 + 6H2O + energy

 

2. The Combustion of fossil fuels

Fossil fuels are made up of hydrocarbons. Hydrocarbons are compounds that contain the elements hydrogen and carbon. Examples are methane, CH4, propane, C3H8, butane, C4H10 and octane, C8H18

Hydrocarbons readily burn or undergo combustion reactions. Combustion may be complete or incomplete.

Complete combustion of fossil fuels results the production carbon dioxide and water. The incomplete combustion of fossil fuels results in the formation of carbon monoxide and soot (carbon).

1. Complete combustion of methane:

Burns with a blue flame

Methane + oxygen carbon dioxide and water

CH4 + 2O2 CO2 + 2H2O

2. Incomplete combustion of methane producing carbon monoxide

Methane + oxygen carbon monoxide and water

CH4 + 1.5O2 CO + 2H2O

3. Incomplete combustion of methane producing soot

Burns with a yellow flame

Methane + oxygen carbon and water

CH4 + O2 C + 2H2O

As the amount of oxygen is decreased from a ratio of 2 to 1.5 to 1 in the above three equations, the combustion products change from carbon dioxide to carbon monoxide to carbon or soot. As the soot is heated in the flame it produces a yellow flame. In real life there is a mixture of carbon monoxide and soot from the incomplete combustion of hydrocarbons as well as unburnt hydrocarbons.

 

Learn how to balance combustions reactions