Molecules

• A molecule is the smallest particle of a compound formed when atoms of elements combines
• The atoms combine together by forming bonds
• When these bonds are formed there are energy changes
• Typically heat energy is given out when the bonds are formed
• While elements contain only one type of an atom
• Compounds contain two/more different types of atoms
• All matter is composed of elements or compounds
• For example Carbon dioxide is a compound of oxygen and carbon
• Each molecule contains one atom of carbon and two atoms of oxygen
• Water is also a compound made up of water molecules
• Each water molecule is made up of one atom of oxygen and two atoms of hydrogen
• Some elements are also made up of molecules
• For example an oxygen atom combines with another to form oxygen molecules
• Hydrogen molecules are made up of two hydrogen atoms

To access more topics go to the Combined Science Notes page.