Difference between revisions of "GCSE Biology Required Practical: Decay of Organic Material"
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==Key Stage 4== | ==Key Stage 4== | ||
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===Meaning=== | ===Meaning=== | ||
Investigate the effect of [[temperature]] on the [[decay]] rate of organic material. | Investigate the effect of [[temperature]] on the [[decay]] rate of organic material. | ||
Latest revision as of 11:27, 13 April 2019
Key Stage 4
Meaning
Investigate the effect of temperature on the decay rate of organic material.
Method
- Independent Variable - Temperature of organic material.
- Dependent Variable - pH of milk.
- Control Variables - Volume of milk, volume of indicator solution.
- Fill a 500ml beaker with 250ml of hot water which will act as a water bath.
- Place 5cm3 of lipase into a testube using a pipette.
- Place 5cm3 of milk into another test tube using a pippette with 5 drops of 'Cresol Red' solution.
- Add 7cm3 of sodium carbonate solution to the milk in the test tube.
- Place both test tubes in the water back and a thermometer into the milk test tube.
- Once the milk mixture has reached the temperature of the water bath add 1cm3 of lipase to the mixture and start a timer.
- Stir throughout then record the time taken for the for the solution to turn yellow.
- Repeat this using different temperatures of water in the beaker.