effect of ph

• Required practical 5


  1. Add iodine to spotting file

  2. Add 2-3 mL of amylase solution

  3. Mix and add starch solution, start stopwatch

  4. After 10 seconds, add a drop of solution to iodine in spotting tile

  5. Repeat every 10 seconds until colour change
• pH 7 buffer


  Used in the experiment
• Starch solution


  Used in the experiment
• Amylase solution


  Used in the experiment
• The less time the iodine solution takes to remain orange-brown

  The quicker all the starch has been digested and so the better the enzyme works at that pH
• Use a water bath at 55 degrees


  • To prove the method
• Colorimeter


  Can be used to measure the progress more accurately
• Changes in the active site of the enzyme when it has denatured

  Relate it to the amount of kinetic energy the molecules have
• pH


  • 5
  • 9
  • 14