Classic Combustion Reaction Experiment
Purpose: Generally in most high school science classes, a combustion reaction is performed where something is burned and the effects are measured. This bi-week, Scientific AmeriKen will reproduce one of these experiments to see whether substances gain or lose weight when burned.

Hypothesis: In any combustion reaction, a hydrocarbon is burned in oxygen to produce carbon dioxide and water. (see below diagram) Because oxygen is being added and converted into the heavier molecules of water and carbon dioxide, then it is hypothesized that the burning of hydrocarbons results in heavier substances.

Equipment: needed for this experiment is a scale, some kind of hydrocarbons (used in this experiment were saltine crackers),  matches, 2 plates, pen and paper.

Procedure: The first step is to weigh the crackers and the plates. Record their weights. Then Burn the cracker and place the plate above the burning cracker to catch the water vapor and place a place below the crackers to catch the any excess substances. Record the final weights and compare.

Objects Massed
Two plates & unburned cracker
14.31 ounces
Two plates & burned cracker
14.26 ounces
Net gain or loss
.05 ounces

Conclusion: Based on the results it would seem that substances lose weight when they are burned. These results contradict the hypothesis, however, it is noted that during testing some of the smoke escaped from the plate, which may account for the loss of weight. Further experimenting should be done on this, however, seeing as it is a usual high school experiment, it was probably not even designed to work right in the first place. 

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