A particular atom will have the same number of protons and electrons and most atoms have at least as many neutrons as protons. An element is a substance that is made entirely from one type of atom. For example, the element hydrogen is made from atoms containing just one proton and one electron.
Keeping this in consideration, how many atoms is an element made up of?
Elements are not made of atoms, but rather, any given atom is a particular element. For example, one atom of the element hydrogen is composed of, minimally, a proton (this would be a hydrogen ion). But it doesn't matter if you have 1 or 100 or 1 trillion atoms of hydrogen, each atom is an element.
Is an atom always an element?
It is NOT always the same as the number of protons and electrons. For example, hydrogen has one proton and one electron, but it doesn't have any neutrons at all! When the number of neutrons is different for individual atoms of the same element, each atom is called an isotope.
What makes up an element?
Solids, liquids, gases, and plasma are all matter. When all atoms that make up a substance are the same, then that substance is an element. Elements are made of only one kind of atom. Because of this, elements are called "pure" substances.