During the last three centuries the science of the substances, the chemistry, has developped from a pseudo-scientific knowledge to a well founded and very deep studied area of human science. A chemistry exam some hundreds of years ago would probably demand from the student the comprehension of the zodiacal calendar, since alchemy – the first contact and intend to identify the essence of matter – was very influenced by the movement of the stars and planets, as believed the savants from those centuries.
The elements from the chemistry periodic table have been appearing very slowly first, and the scientist from the late XVIIIth century began to put order into the chaos. The matter, the substance, has a logic that can be understood, and predicted. Mendeléiev, the famous russian scientist, predicted that there should exist a metallic substance which atomic weight was 26,9815, with 13 of atomic number. Years after, the aluminium was pointed out as the predicted element from Mendeléiev. Of course, today’s high school chemistry is far more profound and complexe than during the past centuries, and as en example, lets say that monsieur Lavoisier wouldn’t feel comfortable by reading any journal of organic chemistry from our days nor would he have it easy by trying to understand the new advances on biochemistry.
That’s because even the smaller and simplest book on general chemistry necessarily has to compile the whole of the knowledge gained in the last years, discoveries that, of course, monsieur Lavosier wouldn't even have reach to imagine. The light that the studies on chemistry have thrown over that field of human science has propelled the economy during the XX century.
