The train between Naples and Sorrento is a very cheap and quick way to travel between the two cities. Unfortunately, it also happens to be one of the worst in terms of pick-pocketing.
Definition of Element. 1) A substance that cannot be decomposed into simpler substances by chemical means. 2) One of the 116 presently known substances that cannot be decomposed by chemical reaction into a simpler substance. Elements comprise all matter at and above the atomic level.
A chemical element is a pure substance which is composed of a single type of atom, characterized by its particular number of protons in the nuclei of its atoms, known as the atomic number and represented by the symbol Z. The mass number is the sum of the number of protons and neutrons in a nucleus.