Compounds

• When elements react, atoms combine with other atoms to form compounds.
• What is a compound?


  A substance composed of two or more elements chemically bonded together.
• Making bonds involves atoms giving away, taking or sharing electron. Only the electrons are involved, the nuclei are not affected when a bond is formed.
• How can you separate the original elements of a compound out again?


  Chemical reaction
• What does a compound formed between a metal and non metal consist of?


  Ionic bond
• During ionic bonding, do the metals lose or gain electrons?


  They lose electrons to form positive ions.
• During ionic bonding, do the non metal atoms gain or lose electrons?


  They gain electrons to form negative ions.
• What does a compound formed from non metals consist of?


  Molecules
• What is bonding of non metals called?


  Covalent bonding
• In a covalent bond, each atom shares an electron with another atom.
• The properties of a compound are usually totally different to the properties of the original elements.
• How can compounds be represented?


  Chemical formulas