(Source: AG Caesar, from Wikimedia Commons.)Įvery atom is made up of three kinds of smaller parts: protons (which are positively charged), neutrons (which have no charge) and electrons (which are negatively charged). The atom does not actually look like this. The diagram shows the parts of a Lithium atom. What makes up an atom? Atoms have protons and neutrons in the center. For example, if you took one water molecule and broke it down, you wouldn’t have water anymore. A water molecule is formed of two hydrogen atoms and one oxygen atom (H2O).Ī molecule is the smallest amount of something you can get without breaking it down into something different. That’s because two hydrogen(H) atoms and one oxygen(O) atom combine to make a water molecule. For example, you might have heard someone call water “H2O”. Molecules are formed when atoms join together. (Source: OpenStax University Physics, via Wikimedia Commons.) This is called the “Periodic Table of the Elements”. Different kinds of atoms, called “elements” are arranged in a table. For example, helium, neon, and gold are each made up of one single kind of atom. You probably already know about some of them. These kinds of atoms are called elements. So far scientists know about 118 different kinds of atoms. Because they are so small, atoms can’t be seen without special tools. The largest one would be about 200,000 times smaller than the width of a human hair. There are many different kinds of atoms, with different names, sizes, and weights*.Ītoms are very tiny. Wow! All of that is possible because of atoms.An atom is the basic unit that everything is made of. Everything you see or imagine is built from something else. Smaller molecules can work together and build macromolecules. As we just learned, there are almost 120 elements that can be found in the molecules we know. Atoms are then used to create the molecules around us. Protons, neutrons, and electrons can then organize to form atoms. Super-tiny subatomic particles are used to create the parts of atoms. If you want to do a little more thinking, imagine the smallest particles of matter. Electrons, protons, and neutrons are the basic subunits for all atoms across the Universe. While atoms from different elements have different masses and structures, they are all built with the same parts. A sodium (Na) atom will always be a sodium atom no matter what molecule it is in. An 'A' will always be an 'A' no matter what word it is in. Molecules are groups of atoms in the same way that words are groups of letters. When you combine them, you can make millions of different molecules. In chemistry, you are working with almost 120 elements. In English, we only have twenty-six letters, but we can make thousands of words. If you read a book, you will find words on each page. We can teach you about the general structure of an atom, but you need to study atoms from different elements to really learn how atoms work. The atom is the smallest unit that has the properties of an element. It would just be an electron doing electron stuff. But what if you only had one electron from a gold atom? That electron would not have the properties of gold anymore. If you only had one atom of gold in your hand, it would have the same properties as every other gold atom in that bar. Because it is pure gold, there are only gold atoms in the bar. You know that bar is made of matter because everything is made of matter. In chemistry, we like to study atoms because the Universe revolves around the properties of elements, not necessarily the properties of an electron or proton.įor example, let’s say you have bar of gold. The electrons in a gold (Au) atom are the same as the electrons in an atom of neon (Ne). However, those smaller particles don’t have the properties of an element. Atoms are made up of smaller and even smaller particles of matter. Atoms are defined as the smallest units of matter that have the properties of an individual element.Īre there pieces of matter smaller than an atom? Sure. In English, you know that “B” is different from “C.” In chemistry, “B” is also different from “C” because boron (B) and carbon (C) are different elements with atoms that have different structures. Elements are the alphabet in the language of molecules.Įach element is a little bit different from the rest. If you want to build molecules, you will need atoms from different elements.

If you want to create a language, you'll need an alphabet. What is an atom? Atoms are building blocks.

Atom vs molecule