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The Father of Modern Chemistry

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The Father of Modern Chemistry The Father of Modern Chemistry Antoine Lavoisier (la-vah-see-ay) was born in France in August 1743. As he entered adulthood, Lavoisier showed brilliance in many fields. He worked in banking, attended law school, and worked as a tax collector. He also experimented with chemistry. Chemistry in the 1700s was very different from chemistry today. Microscopes existed, but they were not powerful enough to view atoms. Many chemists were only slightly familiar with the concept of atoms. In fact, until the 1800s, scientists did not realize atoms are the key building blocks of all matter. When Lavoisier began practicing chemistry, many people still believed in alchemy. Like chemistry, alchemy also focused on matter; Antoine Lavoisier was a French chemist. however, one of alchemy’s main goals was turning He lived from 1743 to 1794. metals into gold. Some chemists also believed in an idea called the phlogiston theory. According to this theory, many materials on Earth contain a material called phlogiston. Chemists thought phlogiston affected a material’s ability to burn. For example, wood burns easily; therefore, chemists thought wood had high levels of phlogiston. Early chemists believed phlogiston was released into the air during burning. To prove their hypothesis, the chemists would weigh an object; the chemists would then burn the object and weigh it again. Because the objects weighed less after burning, the chemists argued that phlogiston was being released from the object. Lavoisier disproved the phlogiston theory. He believed that the weight of objects changed because the substance was reacting with air. Later he proved this hypothesis, which paved the way for another important step in Lavoisier’s career. Discovery Education Science Page 1 of 2 © 2010 Discovery Communications, LLC The Father of Modern Chemistry Lavoisier’s work led him to develop important ideas about mass. Many chemists believed that mass could change during a chemical reaction. Lavoisier’s experiments demonstrated that mass stays the same. Although mass can move or change form, mass is never lost or created. In the case of the burning wood, the wood indeed loses mass. But this mass is moved to the products of the reaction: carbon dioxide and water. This idea is called the law of conservation of mass. According to this law, mass is neither created nor destroyed through ordinary means during a chemical reaction. Matter can change form, but it cannot lose or Lavoisier’s work with burning objects helped gain mass. prove the law of conservation of mass. Imagine a chemical reaction that ends with a piece of metal weighing more than at the start of the reaction. This outcome is possible because the metal combines with another element or molecule that adds to the metal’s mass. Similarly, imagine a chemical reaction that ends with an object weighing less than at the start of the reaction. This outcome is possible because particles of the object change form. Some particles may be released as an invisible gas. Still, the total mass of the products remains the same as the total mass of the reactants. For his work with the law of conservation of mass, many people consider Lavoisier the “father” of modern chemistry. His work changed scientific thinking about chemistry and ushered in a modern era. His work set the stage for a greater understanding of atoms and chemical reactions. The law of conservation of mass also helps explain why chemical equations must be balanced. Lavoisier died in 1794. Like many other French citizens, he was executed during the French Revolution. Discovery Education Science Page 2 of 2 © 2010 Discovery Communications, LLC .
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