Hypothesis: A burning a candle in an enclosed area will deplete the oxygen causing the candle to go out. Choose the answer that would best illustrate step 5 of the Scientific Method: Analyze the results. A. As was predicted in the hypothesis the candle stopped burning when the oxygen inside the the sealed glass box was depleted. The 3" x 5" x 5" box contains 75 cubic inches. If 21% of air is oxygen then we can calculate 15.75 cubic inches of oxygen combined with the carbon and hydrogen in the candle probably forming carbon dioxide and possibly carbon monoxide.
B. The experiment proves that a burning object uses oxygen and that once the oxygen is removed the burning or oxidation process stops. We could reasonably deduce that in order for something to burn there needs to be three elements: heat (match), oxygen (air) and fuel (candle). We made guesses as to what the the oxygen combined with to make new compounds based on previous knowledge of compounds made from the combustion process. To prove what they are we would need to design a new experiment.
C. A candle needs oxygen in order to burn. If a candle burns (oxidizes) in an enclosed space eventually the oxygen in the air will disappear as the O₂ combines with with the compounds in the candle.
D. A candle was ignited with a match and placed inside an enclosed airtight box made of glass, 3" x 5" x 5". A stopwatch was used to time the observation. The candle inside the airtight box started flickering in 3 min. 42 sec. It went out in 4 min. 01 sec.