Our daily lives are filled with the achievements of chemistry, including smartphones, medicines, clothing, food, and energy. Learning chemistry is a key to understanding modern society.
Basic Knowledge
Chemistry is the study of the composition, structure, and properties of substances and their changes (chemical reactions). Since the 20th century, chemistry has developed explosively and produced many chemical products essential to daily life.
For example, the mass production of nitrogen fertilizer using the Haber–Bosch process supports the world's food supply; synthetic dyes and synthetic fibers transformed clothing; and synthetic resins (plastics) are widely used in packaging, construction materials, and electronic devices. The development of pharmaceuticals and semiconductors is also an achievement of chemical synthesis and inorganic materials technology. On the other hand, negative effects such as environmental problems and resource depletion have arisen, so modern chemistry is moving toward green chemistry with an emphasis on “sustainability.”
Chemistry (the study of the composition, structure, properties, and changes of substances)
Haber–Bosch process (nitrogen fixation by N2+3H2 → 2NH3)
Synthetic resin (plastic) (a petroleum-derived polymer compound, such as polyethylene)
Synthetic fiber (a fiber made from petroleum, such as nylon and polyester)
Pharmaceutical (a medicine produced by chemical synthesis or fermentation, such as aspirin and penicillin)
Green chemistry (sustainable chemistry that reduces environmental impact)
Further Study (Background and Significance)
Ancient chemical activities can be traced back to alchemy. Although the goal of turning base metals into gold was not achieved, many experimental techniques, such as distillation, extraction, and crystallization, were developed in the process. In the 18th century, Antoine Lavoisier established the law of conservation of mass, and chemistry became a modern science.
In the 20th century, based on atomic theory and quantum mechanics, chemistry became divided into fields such as organic chemistry, inorganic chemistry, physical chemistry, analytical chemistry, and biochemistry. These fields have transformed society through pharmaceuticals, agricultural chemicals, electronic materials, and fuel cells. In the future, chemistry is expected to help solve global issues through such efforts as carbon neutrality (net-zero greenhouse-gas emissions) and material recycling.
- Chemistry deals with the composition, structure, properties, and changes of substances
- The Haber–Bosch process expanded the world's food supply
- Synthetic fibers and synthetic resins are representative achievements of the 20th century
- Lavoisier established the law of conservation of mass (around 1774)
- Green chemistry = environmentally harmonious chemistry
- Carbon neutrality is a central issue today
- Chemistry supports all aspects of life: medicine, food, clothing, housing, and energy
Points to Note (Easily Confused)
① Chemistry and science are different. Chemistry is one field of science that deals with substances. ② Distinguish between synthetic fibers (petroleum-derived), natural fibers (cotton, wool, and silk), and semisynthetic fibers (rayon and others derived from cellulose). ③ The Haber–Bosch process uses N2 as a raw material and reacts it with H2 to produce NH3. ④ Alchemy was a pseudoscience, but it became the foundation of modern chemistry.
Practice
- What is the method called that produces a raw material for fertilizer from nitrogen in the air?
- Give the English-derived term meaning “environmentally friendly chemistry.”
- Give one example each of a synthetic fiber and a natural fiber.