There are lots of different substances but only just over a hundred elements. An element is a substance that is made up of only one kind of atom. The atoms in a particular element are the same as ...

When two hydrogen atoms get close enough, the electron from each atom feels an attraction from the proton in the other atom's nucleus. This attraction pulls the atoms together. The electrons end up ...

is built of elements—the different types of atoms. They’re billions of years old, most of them, scattered into space by the big bang or exploding stars, then incorporated into the newborn ...

They are formed of simple molecules or individual elements arranged in repeating ... Diamonds, made of carbon atoms, are the hardest natural substance found on Earth. Formed under extremely ...