This very organized yet fun lab that allows students to answer the question, Ã¢ï¿½ï¿½How will an increase in exercise affect the amount of CO2 exhaled?Ã¢ï¿½ï¿½ Students will use BTB(Bromothymol Blue) as an indicator solution that changes color when carbon dioxide (CO2) is bubbled into it. Students will predict whether there will be a difference in the time it takes for the solution to change color before & after exercise? This lab encourages equal particiapation, ensuring each teammate contribute equally to answering questions. Students will work in teams and will also complete a data table & graph. Lab should be completed over 2 or 3 hours.