Cells

• • Cells contain chemicals which react to produce electricity
• • An electrochemical cell is made up of two different electrodes in contact with an electrolyte
• • The two electrodes are metals as they need to be able to conduct electricity
  • The electrolyte is a liquid that contain ions that will react with the electrodes
  • The chemical reactions between the electrodes and electrolyte set up a charge difference between the electrodes
  • If the electrodes are connected by a wire, the charge will flow and electricity is produced
  • A voltmeter can be used to measure the voltage
• • The voltage produced by a cell is dependent on the type of electrode and electrolyte
  • Different metals will react differently with the same electrolyte
  • The bigger difference in reactivity of the electrodes, the bigger the voltage of the cell
• • The electroyte used in a cell will affect the voltage as different ions will react differently with metal electrodes used