Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Measuring Differences in Carbon-dioxide production Bromothymol blue (BTB) is an indicator that changes color in the presence of acids or bases. It is blue in the presence of a base and yellow in the presence of an acid. Carbon-dioxide will alter the color of BTB in water (CO2 + H2O H2CO3). You can use a titration technique to compare the amount of carbon dioxide produced by a person at different levels of physical activity. SAFETY: BTB will stain clothes and skin. NaOH (sodium hydroxide) is corrosive and poisonous. Wear safety goggles. Wash with soap and water immediately if your skin comes in contact with either substance, and inform the teacher. Titration procedure: Use a straw to exhale air into the solution of BTB. Do not blow too forcefully, or it will bubble out. Make sure you do not inhale. After the solution changes colors, practice changing it back again by adding drops of sodium hydroxide. Swirl the solution after you add each drop—sometimes the color change is delayed. The more drops of NaOH needed, the greater the amount of CO2 exhaled in the container. Your assignment: How does the amount of carbon dioxide a person exhales change as a result of physical activity? As a group, develop a hypothesis and design an experiment to test your hypothesis. You may use one or all of your group members as guinea pigs. Take into account controls and variables. Enough data should be taken to form conclusions. You may want to take averages or compare with other groups. You will turn in a lab report that should follow the AP lab report format. Measuring Differences in Carbon-dioxide production Bromothymol blue (BTB) is an indicator that changes color in the presence of acids or bases. It is blue in the presence of a base and yellow in the presence of an acid. Carbon-dioxide will alter the color of BTB in water (CO2 + H2O H2CO3). You can use a titration technique to compare the amount of carbon dioxide produced by a person at different levels of physical activity. SAFETY: BTB will stain clothes and skin. NaOH (sodium hydroxide) is corrosive and poisonous. Wear safety goggles. Wash with soap and water immediately if your skin comes in contact with either substance, and inform the teacher. Titration procedure: Use a straw to exhale air into the solution of BTB. Do not blow too forcefully, or it will bubble out. Make sure you do not inhale. After the solution changes colors, practice changing it back again by adding drops of sodium hydroxide. Swirl the solution after you add each drop—sometimes the color change is delayed. The more drops of NaOH needed, the greater the amount of CO 2 exhaled in the container. Your assignment: How does the amount of carbon dioxide a person exhales change as a result of physical activity? As a group, develop a hypothesis and design an experiment to test your hypothesis. You may use one or all of your group members as guinea pigs. Take into account controls and variables. Enough data should be taken to form conclusions. You may want to take averages or compare with other groups. You will turn in a lab report that should follow the AP lab report format.