The rate of reaction can be determined using the formula:Rate of reaction = change in concentration / change in time First, we need to find the change in concentration of hydrogen peroxide. The balanced equation for the decomposition of hydrogen peroxide is:2H2O2 2H2O + O2From the stoichiometry of the reaction, we can see that for every 2 moles of hydrogen peroxide, 1 mole of oxygen gas is produced. So, if 0.02 moles of oxygen gas are produced, the amount of hydrogen peroxide decomposed is:0.02 moles O2 2 moles H2O2 / 1 mole O2 = 0.04 moles H2O2Now, we need to find the change in concentration of hydrogen peroxide. Since the initial concentration is 0.1 M, we can calculate the final concentration as follows:Final concentration = Initial moles - Decomposed moles / VolumeWe are not given the volume, so we can use the variable V for the volume:Final concentration = 0.1V - 0.04 / VNow, we can find the change in concentration:Change in concentration = Initial concentration - Final concentrationChange in concentration = 0.1V - 0.1V - 0.04 / VThe change in time is given as 30 seconds. Now we can find the rate of reaction:Rate of reaction = change in concentration / change in time Rate of reaction = 0.04 / V / 30Since we don't have the volume, the rate of reaction can be expressed as:Rate of reaction = 0.04 / 30V M/s