. Three students are asked to discuss why the CO2 produced from the reaction
rose upward out of the mouth of the test tube even though CO2 is denser than
air. Select the student that employs correct scientific reasoning.
Student 1: The reason the carbon dioxide rose despite being denser than air is because the heat
caused it to condense.
• Student 2: The carbon dioxide produced by decomposition of baking soda was able to rise above
the air because the oxygen in the test tube was consumed.
• Student 3: The carbon dioxide rose up because the heat expanded the gas and it became less
dense.
O Student 3
OStudent 1
O Student 2