6th Grade · Science · Activity · shared by Luke Morgan
Explore Lavoisier's ice calorimeter experiments and respiration with this free 6th Grade Science activity. Learn how he measured body heat.
The Chemistry of Life: Lavoisier’s Breakthroughs
How do our bodies stay warm, and what happens when we breathe? For centuries, these were some of the biggest mysteries in science. In the late 1700s, a scientist named Antoine Lavoisier used precise tools and careful measurements to find the answers. Read the following passage to learn how his experiments with ice and oxygen changed our understanding of life itself.
Antoine Lavoisier was a pioneer who believed that chemistry required exact measurements. To study how living things produce energy, he helped invent a device called the ice calorimeter. This machine had three specific layers. The outer layer was filled with ice to block out the warmth of the room. The middle layer also held ice, which would melt whenever a heat source was placed inside the center. By weighing the water that dripped from this middle layer, Lavoisier could calculate exactly how much heat an animal produced. He discovered that a guinea pig placed in the center consistently melted a specific amount of ice over time.
During these experiments, Lavoisier also measured the gases the animal used and created. He noticed that the guinea pig consumed a gas called oxygen from the air. At the same time, the animal released a different gas known as carbon dioxide. Lavoisier realized that this process, which we call respiration, was actually a form of slow combustion. Just as a candle burns fuel to create a flame, animals "burn" nutrients to create body heat. His data showed a direct connection: the more oxygen an animal consumed, the more heat its body generated. This discovery proved that life depends on chemical reactions to create the energy that keeps us warm and active.
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