Book excerpt: Excerpt from Foundations of Chemistry A chemical change takes place when a substance, or substances, undergoes a change into a new substance, or substances, with widely different properties. Chemical changes usually involve the production of or the absorption of a large amount of heat. The burning of charcoal is one of the best known and most typical of chemical changes. Conservation of Matter: The amount of matter in the universe is constant; matter is not created or destroyed. This statement is known as the law of the conservation of matter. Physical changes are those in which bodies of substance are changed in any way without being altered in their chemical nature. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.