Chemistry is the science that studies the composition and changes in composition of the substances around us. Man's natural curiosity about the things and transformations that he observed was the original impetus for the development of this science, but its true beginning was in the work of the alchemists of the Middle Ages. These men searched for a way to change the base metals such as lead into gold. In the large span of time since then, chemistry has developed into a true science and we have amassed a tremendous volume of knowledge. To facilitate the study of chemistry, we can divide it into two divisions: Inorganic chemistry, which deals with the elements and mineral materials, and organic chemistry, which deals with compounds containing carbon. More divisions of chemistry exist, but we will be primarily concerned with these two.