Decay: Required Practical

• 1. Fill half of a beaker with hot water from a kettle to act as a water bath
• 2. Use a syringe to transfer 5cm3 of lipase solution into a boiling tube and label it 'lipase'
• 3. Add 5 drops of phenolpthalein into another boiling tube and label 'milk and use a pipette to transfer 5cm3 of milk into the 'milk' tube
• 4. Using another pipette, transfer 7cm3 of sodium carbonate solution into the 'milk' tube, turning the solution pink. Then place a thermometer in the 'milk' tube and place both boiling tubes in the water bath
• 5. Once both tubes have come up to the same temperature as the water bath, transfer 1cm3 of lipase into the 'milk' tube and start timer immediately, recording how long it takes for the solution to turn back to white in a table
• 6. Repeat experiment at the same temperature twice and calculate the mean. Repeat using a range of temperatures of water baths and plot a graph of time against temperature