Investigating enzymatic reactions

• What is the first step?

  Put a drop of iodine solution into every well of a spotting tile.
• What is the second step?

  Place a bunsen burner on a heat proof mat, and a tripod and a gauze over it. Put a beaker of water on top of the tripod and heat the water until it is 35 degrees.
• What can you use to measure the water?

  Thermometer
• What do you need to keep constant?

  The temperature of the water.
• What is the third step?

  Use a syringe to add 1cm of amylase solution and 1cm of buffer solution with a pH of 5. Using test tube holders, put the tube into the beaker of water and wait 5 minutes.
• What do you do in the 4th step?

  Use a different syringe to add 5cm cubed of a starch solution to the boiling tube.
• What is the 5th step?

  Immediately mix the contents of the boiling tube and start a stop clock.
• How would you use continuous sampling?

  Use a dropping pippete to take a fresh sample from the boiling tube every 30 seconds and put a drop into the well.
• When the iodine solution remains browny orange, starch is no longer present
• What can you do after you’ve done?

  Repeat the whole experiment with buffer solution of different pH values to see how pH affect the time taken for starch to be broken down.
• What would a control variable be?

  Volume and concentration of amylase solution.
• How do you calculate the rate of a reaction?

  Rate = 1000 divided by time