Measuring the Effect of Enzyme Concentration

LAB: ENZYME ACTIVITY

MEASURING THE EFFECT OF ENZYME CONCENTRATION

Safety Alert:

1.  Wear goggles at all times

2.  Do not eat or drink in the laboratory (NO GUM)

3.  Avoid unnecessary contact with chemicals

Problem: What effect does increasing the concentration of catalase have on the rate of decomposition of hydrogen peroxide?

Hypothesis: Write an If….., then… statement on your journal

Variables: MV and RV---write both of them in your journal

Materials (do not write in journal)

5 filter paper disks catalase stock solution

Forceps small disposable cups

Scissors timing device

Small beakers 1.5% hydrogen peroxide (H2O2)

15mL distilled water gloves, aprons, and eye protection

Paper towels marking pen

10% hydroxylamine hydrochloride solution

Observations:

Data Table
% Catalase / Time in Seconds
Trial 1 / Trial 2 / Trial 3 / Average
100
50
0
100% plus
hydroxylamine

Analysis: Create a graph to show your data

Conclusion Questions—Write in COMPLETE SENTENCES

1.  What causes the disks to float to the surface?

2.  Which concentration of catalase had the fastest reaction time?

3.  Which concentration of catalase had the slowest reaction time?

4.  What type of biological molecole is catalase?

5.  What does catalase do to hydrogen peroxide?

6.  Based on the graph and overall slope of the line, what can you conclude about the effect of enzyme concentration on reaction time?

7.  How would the results be different if you repeated Part I of this experiment using water instead of hydrogen peroxide? (THINK ABOUT THE CHEMICAL REACTION GOING ON)

8.  Describe the effect hydroxylamine hydrochloride has on the reaction time.

9.  A student forgets to dry the tip of the forceps after dipping the disk in catalase solution. What effect will this error have on the rate of the reaction for that trial? Explain

10.  Using Figure 1 on the prelab sheet, draw an imaginary cycle creating your own enzyme (ase), your own substrate (ose), active site, and be descriptive on the ends that pair up to active site from the substrate. Label all parts of the cycle. Be Creative with Names