The difference between the neutron number and the atomic number is known as the neutron excess: D = N – Z = A – 2Z.įor stable elements, there is usually a variety of stable isotopes. Neutron number plus atomic number equals atomic mass number: N+Z=A. The total number of neutrons in the nucleus of an atom is called the neutron number of the atom and is given the symbol N. The total electrical charge of the nucleus is therefore +Ze, where e (elementary charge) equals to 1,602 x 10 -19 coulombs. Total number of protons in the nucleus is called the atomic number of the atom and is given the symbol Z.
Boron, similarly, does not make for a dependable, stable base structure.Atomic Number – Protons, Electrons and Neutrons in CarbonĬarbon is a chemical element with atomic number 6 which means there are 6 protons in its nucleus. Nitrogen has five valence electrons so generally only forms 3 single bonds, limiting its usefulness. No other element can quite do what carbon does: Silicon has the ability to form four bonds with other atoms but those bonds tend to be weak due to the additional electron shell in a silicon atom. Carbon is like the classic 6 peg Lego in that it is a widely used building block in molecules. Some Lego blocks are very limited in their use, while others are versatile for basic building. In a similar fashion Carbon can make 4 bonds, with varying geometry and generally stable structures. It has the features that make it an ideal basic building block for the construction of a wide variety of larger, complex shapes necessary for biological function. The 6-pin Lego is able to make lots of other connections, and also can make strong, stable connections. But the larger organic molecules can contain hundreds or thousands of carbons, linked with rings and bridges and other complex structures that fold into particular three-dimensional structures.Ĭarbon is a bit like a basic Lego building block. Small organic molecules might contain just one or two carbon atoms surrounded by other atoms. The architecture of carbon structures is therefore fantastically varied. Amoxicillin, C16H19N3O5S Benjah-bmm27, Public domain, via Wikimedia Commons It readily bonds with other atoms such as oxygen, nitrogen and hydrogen, forming quite stable arrangements with these common elements as well. The four valence electrons in a carbon atom can do this by forming four single bonds, or by forming two single bonds and a double bond, by forming one single bonds and a triple bond, or by forming two double bonds.Ĭarbons covalently bond with one another, also, forming chains of various lengths, and rings. Carbon does however readily engage in covalent bonding, sharing electrons with neighboring atoms and forming tight associations with them. So while a carbon atom can be ionized through either the gain or loss of electrons, it does not tend to do so. The outer shell has four electrons that are held quite strongly by the electrostatic pull from the nucleus. The nucleus contains 6 positively-charged protons, and there are 6 electrons outside the nucleus distributed into two shells. Carbon, atomic number 6, is an element with atoms that are small and relatively simple.