What is an Atomic Number?
The atomic number of an element is equal to the number of protons in the nucleus of an atom of the element. Protons are positively charged particles found in the center of every atom. Each element has its own unique number and is differentiated from one another by the number of protons it has. The nucleus of an atom may also be home to neutrons, but the number of neutrons has no bearing on the element’s atomic number. Electrons reside just outside of the nucleus and also have no bearing on the number. Some confusion may exist between the atomic number and atomic mass of an element, but these two terms should not be confused. While atomic number is the number of protons an atom has, the atomic mass is the sum of number of protons and neutrons in the atom. Hydrogen, for example, has an atomic number of one because it has one proton. Deuterium, an isotope of hydrogen, has one proton and one neutron. If the atom had two protons, it would not be hydrogen but helium. Atomic number can be fou
The atomic number of an element is the number of protons that exist in the nucleus of at atom. The number of protons dictates what the atom is. For example hydrogen has an atomic number of 1, if somehow we were to add one proton to a hydrogen atom, it would become helium, which has an atomic number of 2. If an atom has a neutral charge it would have the same number of electrons as protons, and thus the atomic number would also be in reference to the number of electrons in an atom. We have been able to create elements that are not naturally occurring on Earth by figuring out ways to add or subtract the number of protons in a certain element. Here’s a picture of the periodic table which sorts elements by their atomic number.
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