Observations and results
After one week of mummification did the hot dog look darker in color, smell bad and shrink slightly? After two weeks did the hot dog look about the same and shrink only a tiny bit more, if at all?
Baking soda is a desiccant, which is a substance that dries out things close to it. It does this by absorbing moisture from its surrounding environment. The baking soda should have absorbed the moisture from the hot dog, desiccating (drying) it. (Fresh baking soda is needed because older baking soda will probably not be as effective, having already absorbed moisture from its surrounding environment.) As the hot dog lost moisture, it changed color, smelled bad and shrank, with the most significant changes (and moisture loss) being observed after one week and only smaller (if any) changes after two weeks total. For example, you may have seen that the hot dog became about 4 percent shorter and 25 percent smaller in circumference after one week, and about 6 percent shorter and only 27 percent smaller in circumference after two weeks total compared with its original condition. It may not have noticeably changed in color or smell after two weeks compared with its condition after the first week.
Do not eat the mummified hot dog! It can be disposed of in the trash.
More to explore
Secrets of the Pharaohs, from PBS
Mummification, from The British Museum
Mummy Maker, from Discovery Kids
Minding Your Mummies: The Science of Mummification, from Science Buddies
This activity brought to you in partnership with Science Buddies