IN his studies of the relative frequency of the different elements composing the crust of the earth, Mr. F. W. Clarke supposes that to a depth of ten miles below the level of the sea the ...

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 ...

There are 17 rare earth elements (REEs) in all — 15 lanthanides plus yttrium and scandium. It's a fairly diverse group, with ...

Scientists have found that our bodies need 28 different elements to function properly. These are almost one-quarter of the periodic table and are mainly found in the first four periods.

Sulfur is another element. It contains only sulfur atoms, and nothing else, so it is pure. When we mix two different pure substances together, like this, it’s a mixture. This is now a mixture of ...