SIMPLE DEMONSTRATIONS OF THE ENERGY EXCHANGE BETWEEN SYSTEM AND ITS SURROUNDING

Abstract

Demonstrating of energy changes is performed by observing physical or chemical changes that are started in the system in contact with the reaction vessel, in which heating or cooling takes place. The procedures for two short experiments in high school general chemistry course (age of 15) are described: (i) hydration of unslaked lime – melting of ice; and (ii) hydration of sulphuric acid − ether cannon. The demonstrations enable active acquiring of thermochemistry concepts. [Chem. Educ. Res. Pract. Eur.: 2001, 2, 329-332]