This week we’re going to start learning about the periodic table of elements!

What’s an element? Well, first we need to know what an atom is. Atoms are the incredibly tiny building blocks of everything around us. But not all atoms are the same. Some are big and heavy, and some are small and light. At the center of an atom is the nucleus, which is made up of tinier particles called protons and neutrons. Whizzing around the nucleus are even smaller particles called electrons.

It turns out that atoms that have the same number of protons in their nucleus all behave pretty much the same. So, we can sort atoms by how many protons they have! Scientists have given each type of atom a silly name so they can keep them straight in their heads. If an atom has 6 protons, for example, they call it carbon. If it has 8 protons, they call it oxygen. If it has 79 protons (no more, no less!) it’s gold, and if it has 2 protons it’s helium! We say each of these different types of atoms is an element.

On Earth, there are about 90 different elements. Scientists have created about 20 more in labs, but most of them aren’t stable and break apart into smaller atoms really quickly. That’s a lot of elements, so to keep them organized, a Russian chemist named Dmitri Mendeleev invented a way of categorizing them in a table. When he created his periodic table, he put similar elements together in columns, and realized that there were several gaps where he thought an element should be, but hadn’t been discovered yet. Mendeleev was a smart guy–later on, several new elements were discovered that filled in the gaps in his table, and behaved just how he said they should!

Although all the matter around us is made of elements, a lot of elements don’t like to be by themselves. In fact, most things are made of different types of elements connected together, kind of like different LEGO bricks stuck together to make a spaceship. If the elements are like LEGO bricks, the spaceship is a chemical, or a molecule.

Whew, that was a lot of information! Good job for making it this far! Now for some fun…

A crazy college professor in England has made a bunch of videos showing what different elements are like. You can see them here! Below is the video for oxygen. Bet you didn’t know that oxygen was magnetic! Or that fluorine (the element in fluoride toothpaste) is extremely dangerous when by itself!

If you have any questions about elements or the periodic table, leave a comment!

-Mr. J