What I learned is that a element is one of the parts of which something is made up. The simplest form of matter. Also, that an acid is a compound or substance that increases the concentration of hydrogen ions. The one thingI liked the most was the lab when we put all of the elements together and the bag blew up. The thing I didn't like the most about this lesson was that we had to do so many papers=http://! What is an ion???