Practical: Enzymes and Reactions

Only available on StudyMode
  • Topic: PH, Mortar and pestle, Temperature
  • Pages : 5 (874 words )
  • Download(s) : 186
  • Published : February 12, 2012
Open Document
Text Preview
Temperature and Enzyme Activity

Aim: To investigate the effect of temperature on enzyme activity

Hypothesis: As the temperature deviates from 40°C the activity will lower

Equipment:
– Chemicals:
– Milk
– Junket tablets
– Hot water
– Ice
– Test tubes
– Stopwatch
– Measuring cylinder

Risk Assessment:
|Hazard |Risk |Prevention | |Hot Water |Hot water splashing or spilling on |Safety glasses and aprons were worn | | |skin | | |Glassware |Cutting one’s self on broken |Safety glasses and aprons were worn | | |glassware | |

Method:
1. Junket tablet was crushed in a pestle and mortar and measured into 5gram portions. 2. Prepared beakers with water at temperatures 20, 30, 40, 50 and 60 degrees Celsius using Crushed ice to sustain the lower temperatures and adding hot water to reach higher temperatures. 3. 10mL of milk was poured into the test tubes using the measuring cylinder for accurate amounts then label the test tubes to indicate what temperature they will be subjected to and if they are to receive the enzyme. 4. Place 2 test tubes in each of the Beakers – one to receive the enzyme and one as a control. A thermometer was placed in each test tube. 5. The Junket was added and the timer started, tipping the test tube once every test seconds to monitor progress. 6. The timer was stopped when the Milk coagulated and the time was recorded.

Results:
|Temperature (°C) |Time Taken | |20 |NR (22 min +) | |30 |NR (22 min +) | |40 |9 min 42 sec | |50 |3 min | |60 |NR (22 min +) |

Controls did not have a reaction

Conclusion: As the temperature deviates from 50°C the activity lowered pH and Enzyme Activity

Aim: To investigate the effect of pH on enzyme activity

Hypothesis: As the pH deviates from 7 the activity will lower

Equipment:
– Chemicals:
– Milk
– Junket tablets
– Hydrochloric Acid (HCl)
– Sodium Hydroxide (NaOH)
– Test tubes
– Stopwatch
– Measuring cylinder

Risk Assessment:
|Hazard |Risk |Prevention | |Acid/Base |Getting harmful chemicals on skin or eyes |Aprons and eye protection was worn | |Glassware |Cutting one’s self on broken glassware |Safety glasses and aprons were worn |

Method:
1. Junket tablet was crushed in a pestle and mortar and measured into 5gram portions. 2. Prepared beakers with water with pHs of 1, 4, 6, 8 and 12 degrees Celsius using HCl to lower pH and NaOH to raise pH levels. 3. 10mL of milk was poured into the test tubes using the measuring cylinder for accurate amounts then label the test tubes to indicate what temperature they will be subjected to and if they are to receive the enzyme. 4. Place 2 test tubes in each of the Beakers – one to receive the enzyme and one as a control. 5. The Junket was added and the timer started, tipping the test tube once every test seconds to monitor progress. 6. The timer was stopped when the Milk coagulated and the time was recorded.

Results:
|pH |Time Taken | |1 |NR | |4...
tracking img