Enzyme Lab Effects of pH

By: Alex Rafael C. 1st


What affect do enzyme concentration and pH balance have on enzyme activity?

Identification of Variables

The Independent variable is time, which is measured in seconds.

The Dependent variables are enzyme concentration and pH.

The Constant was what the enzymes were composed of.


Any change in the amount of pH over a period of time will be dependent on the level of concentration in enzymes present.


LabQuest Enzyme Suspension

LabQuest app Four 18 x 150 mm test tubes

Vernier Gas Pressure Sensor Ice

rubber-stopper assembly pH Buffers

10 mL graduated cylinder Test Tube Rack

250 mL beaker of water Thermometer

Hydrogen Peroxide Four Disposable Pipettes

Styrofoam Cup Logger Pro


For Enzyme Concentration:

1. Wear Goggles

2. Connect plastic tubing to the valve on Gas Pressure sensor.

3. Connect Gas pressure sensor to LabQuest and choose new from the file menu.

4. Add 2, then 3, then 4 drops to each separate test tube respectively.

5. Record data of enzyme activity using gas pressure sensor.

6. Graph Data


At a pH of 7, the enzyme was in its prime state. At a pH of 10, the enzyme denatured and the graph and stats began to decline.