When animals (like you) exhale, they release the waste product carbon dioxide (CO2). If Carbon Dioxide is added to water, it forms an acid called carbonic acid. We can measure how much carbon dioxide has been released by using a pH indicator called bromthymol blue. This indicator is blue in a neutral solution (pH 7) but turns yellow in an acidic solution. If a basic solution is added back to the acidic solution, the solution can be neutralized back to the original pH. How much base is added to neutralize the acid can be used to determine the amount of carbon dioxide that what added to the water. Many factors effect respiration rate. Exercise, age, size, health, can all effect the efficiency of the respiratory system.
Purpose: To determine the resting carbon dioxide release in a typical high school student.
To determine other factors that might impact the amount of carbon dioxide released.