The Hot and Cold of It

Humans rely heavily on information from visual stimuli to draw inferences and make judgments about a situation. What happens if our senses deceive us? Sometimes the signals we receive (or perceive) in chemistry lab can cause us to draw the wrong conclusions about a chemical reaction. This demonstration pairs two different chemical reactions with opposite and unexpected temperature changes. The first mixture appears to bubble and “boil,” but the temperature actually drops. In the second reaction, a solution appears to “freeze,” and the temperature rises dramatically.