Me with chemistry. a chemistry class sets up nine test tubes and places different masses of mno2 in each test tube. an equal amount of h2o2 is added to each test tube and the volume of gas produced is measured each minute for five minutes. the gas recorded is the total gas produced up to that point not what is produced that minute 1.what is the constant in the experiment? 2.what is the independent variable? 3. what is the dependent variable?