Students

1

• Students
• Get handout Enzyme Lab
• Food drinkput aside on back tables..thank you
• Cell phones in bin.muted or off.please thank
  you

2
Lab 2 Enzyme catalysis Guaiacol
2H2O2 tetraguaiacol 8H2O
(colorless) (brownish orange) Enzyme
peroxidase Substrate peroxide (H2O2) How will
we measure enzyme function? - Color change using
a spectrophotometer
3

• How does a spectrophotometer work?
• Take home points
• Light at a specific wavelength is sent through a
  liquid sample
• Light passing through the sample is detected on
  the other side
• To measure this accurately, we must calibrate
  (blank) the spec.
• Calibrating the spec sets the range tells the
  spec
• what 0 light is (darkness)
• what 100 light is (all light passing
  through.the blank tube)
• For our experiment we will see how the amount of
  light passing through the test tube changes as
  the reaction proceeds.

4
Tube 1 (blank) Tube 2 Tube 3
Guaiacol 0.1 mL (2 drops) 0.1 mL (2 drops) ---
H2O2 --- 0.2 mL (4 drops) ---
Turnip extract (peroxidase) 1.0 mL (20 drops) --- 1.0 mL (20 drops)
dH2O 5.2 mL 5.0 mL ---

1. Set wavelength to 500 nm
2. With the chamber empty, use left knob to adjust
   to 0 T
3. Insert tube 1 (blank) into spec use right knob
   to adjust to 100 T
4. Pour 2 into 3 begin timing immediately!!
5. Invert 2X quickly place into spec
6. Record T every 10 sec for 90 120 secs
7. From page 3, choose your experiment for tomorrow
8. Peel tape, rinse tubes place in tan basin by
   sink. Thank you!
9. Graph data together on 1 graph calculate
   reaction rates of each line

5

• Students
• Food drink away or on back table
• Lab notebooks MONDAY Osmosis/diffusion
  Enzyme
• Tomorrow Friday in Mercers Rmso his students
  can do this lab
• Today do the experiments you designed!
• Cell phones in bin.muted or off.please thank
  you
• Osmosis/diffusion
• Pre-lab can be same for both
• Purpose/overview
• Personal Acct
• Diffusion
• Procedure paraphrased
• Data table
• Osmosis
• Procedure
• Your data class data

6

• Enzyme Lab
• Pre-lab
• Enzyme info
• Spec info
• The Reaction we measured
• Purpose/overview
• Personal Acct
• Day 1
• Procedure with ingredient table
• Data table
• Graph rxn rate
• Day 2
• Elements of Good Experimental Design
• Procedure with ingredient table
• Data table
• Graph reaction rates
• Discussion question
• Conclusion
• What did you learn?