What are atoms made of? Why is everything made of atoms? Why are atoms so small? How many atoms are there in the world? How did scientists find atoms if we can鈥檛 see them? How do atoms get their color? We learn about atoms with , author of 鈥淧article Physics Brick by Brick鈥� and 鈥淭he Secret Life of the Periodic Table.鈥� His new book, 鈥淗ow the Universe Works,鈥� will be released in September.
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- Atoms are the building blocks of the molecules around us. All matter is made of atoms.
- There are different types of atoms. They鈥檙e known as elements, basic substances that can鈥檛 be broken down into smaller particles by any normal chemical reactions. Scientists have found 118 elements, and they鈥檙e organized in the Periodic Table of Elements by their atomic number, which is the number of protons in the atom鈥檚 nucleus. The atomic number is unique to each element.
- There isn鈥檛 a way to distinguish between different atoms of the same element. So all carbon atoms are the same, whether they鈥檙e inside you and me, or inside the wood of a tree.
- For a long time, scientists thought that atoms were the smallest unit. But they later discovered that atoms are made up of a nucleus that contains protons and neutrons, and electrons that float outside the nucleus.
- Protons and neutrons can be divided into even smaller units called quarks. (So far, electrons haven鈥檛 been found to be able to be divided into smaller subatomic particles.)
- How many atoms are there in the world? One estimate is 10 to the 50th! That鈥檚 100,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 atoms!
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