Illustrated Guide to Home Chemistry Experiments

Chapter 12 Laboratory: Chemical Kinetics 225

oALIpToN ACTIvITIES

If you have time and the required materials, consider performing these optional activities:

• Graph your results for the trials to determine whether the reaction rate is linear.


• Repeat the trials, using more concentrated catalase solution (or more of it) and
  determine the effect of additional catalyst on the reaction rate.


• Boil a solution of catalase for 30–60 seconds and then use the boiled catalase
  solution to determine whether the catalase enzyme is denatured by heat.


• Test other materials such as manganese dioxide, copper(II) oxide, and zinc oxide to
  determine whether they function as catalysts for the decomposition of hydrogen
  peroxide and, if so, how efficient each is compared with each other and with catalase.

dISoALp S :

All waste solutions from

this laboratory session can

be disposed of by flushing

them down the drain with

plenty of water.

TABLE 12-4: Effect of a catalyst on reaction rate—observed and calculated data

Hydrogen peroxideReaction timeTitrant volumeTitrant millimolesPeroxide remainingReaction rate

A. ________.____ mL 0.0 s________.____ mL________.____ mM________.____ mM n/a

B. ________.____ mL________.___ s________.____ mL________.____ mM________.____ mM________.____ mM/s

C. ________.____ mL________.___ s________.____ mL________.____ mM________.____ mM________.____ mM/s

D. ________.____ mL________.___ s________.____ mL________.____ mM________.____ mM________.____ mM/s

E. ________.____ mL________.___ s________.____ mL________.____ mM________.____ mM________.____ mM/s

F. ________.____ mL________.___ s________.____ mL________.____ mM________.____ mM________.____ mM/s

Beaker

RQEWEvI UESTIOnS

q 1 : What effect did you observe the catalase catalyst to have on reaction rate?

q: 2 Based on the data you recorded in Table 12-4, is the effect of the catalyst on reaction rate linear? If not, propose an explanation.