Lab Experiment

The purpose of this lab was to determine if a there is a change in mass when a gas is produced and determine if gas has mass. To conduct this experiment, the group must be careful not to let the Alka-Seltzer tablet get wet before the bottle is closed by wiping the lip of the bottle and the cap so it remains dry, or risk gas escaping into the air and not being captured by the bottle. Also, the group must be sure to close the bottle tightly with the cap, because gas may escape this way as well. During this investigation, it was determined that there is 0 change in mass when a gas is produced, because the mass of the bottle, water, Alka-Seltzer tablet, and cap remained the same even after the Alka-Seltzer had a chemical reaction with the water and
While some groups got different results, most were within the range of the sensitivity of the balance. With the exception of one outlier, the overall trend of the class was that there is 0 change in mass when a gas is produced. This suggests that there is no change in mass when a gas a produced in a closed system, which supports the Law of Conservation of Mass. This law states that the mass remains the same throughout all changes provided it is in a closed system. Although the class did not compare the data from when the gas was released, looking at the group’s data which shows a decrease after the gas is released, the group can conclude that gas has mass. A possible error that may have been encountered is that the group accidentally got the Alka-Seltzer tablet wet before closing the bottle, causing the gas that would be produced to escape into the outside air. This error would have caused the group to have an apparent decrease in mass because the gas escaped. Another possible error is that the group did not screw the lid on tightly enough to the bottle, allowing the gas to escape through the