In the first experiment, it took 32 minutes for all of the Mg to react. In the second experiment, it took 54 minutes for all of the Mg to react. Which of the following could account for the change in reaction rate of the second experiment?

A.
a catalyst was added
B.
the Mg was powdered into H2
C.
the H2 was decreased
D.
the temperature was decreased

You exhale co2 which is produced during cellular respiration.  co2 combines with the water in your blood's plasma to make up one half of the body's most important buffer pair, carbonic acid.  the more physical activity you engage in, the more co2 your body is producing.  you can see this by putting some of the cabbage indicator in a glass and then blowing bubbles into it through a straw.  can you see a change in the color of the indicator?