Effect of an Inhibitor on Foam Height
1. Add potato pulp to a depth of about 3 cm to a
fourth graduated cylinder. Add
10 drops copper(II) sulfate solution to the cylinder and stir.
2. Place 10 mL 3% hydrogen peroxide in a separate
graduated cylinder.
3. Place both cylinders in a water bath at 20 °C for
about 5 min.
4. Remove the cylinders from the water bath and add
the 3% hydrogen peroxide
to the potato pulp mixture.
5. Measure the foam height after 5 min. How does the
foam height compare to
that produced above without the copper(II) sulfate added?
6. Thoroughly wash your hands before leaving the
laboratory.
Data Analysis
1. According to the data you plotted on Graph 1,
how does the quantity of foam
produced by the breakdown of hydrogen peroxide vary with time?
2. Your teacher will ask you to plot your data for
temperature vs. height of foam
on a master graph along with the data from your classmates.
According to data plotted on the master graph, what is the effect
of
temperature on the rate of enzymatic action? At some point, did
the quantity
of foam not increase as temperature increased? How can you
account for this?
3. According to your data, what effect did adding an
inhibitor [copper(II) ions]
have on the rate of foam production? Did the production of foam
cease
completely? How can you account for this?
