A mixture is two or more substances which have been combined such that each substance retains its own chemical identity. An example of this that we did in class is the cornstarch and water mixture. These elements did not change. You can also draw out your original ingredients easily(-ie they will eventually turn back into cornstarch and water.)
A bond is different in that it is two or more substances that when combined create a new substance (with new chemical makeup). We did this experiment when we mixed the water, glue and borax soap solution that made a chemical bond called a polymer. Also you cannot draw out the original ingredients because they have already reacted chemically (unless you chemically pull them apart).
Ok, we also did a crystal garden, right? "Table salt (NaCl) can be dissolved in water. The amount of salt in a particular quantity of water depends on its temperature - more being soluble in warmer water.
ReplyDeletePeople who live near the ocean often transfer sea water to open pools where evaporation can take place. This is still done in the Hawaiian Islands where there is an extended dry season.
As water evaporates, some of the salt cannot be retained and crystals of salt form along the edges of the pools and finally when all the water is gone there will be crystals on the bottom of the dried pool. These need only purification to be used as table salt." Stewert's web site.