Therefore, the atomic mass of sodium can be taken as 23. Now, round up this figure to get the nearest whole number. The atomic mass of sodium, as mentioned in the sodium box given above is 22.989. Number of neutrons = Atomic mass (rounding it up to the nearest whole number) – Number of protons The formula for finding the number of neutrons in an atom is given as follows: Now, we shall calculate the number of neutrons present in the nucleus of the sodium atom. Hence, for the sodium atom, Number of protons = Atomic number =11 In the case of the sodium atom, the atomic number is 11. The number of protons is always equal to the atomic number of an atom. To draw the Bohr model of sodium we must first find out the number of all the atomic particles present in the sodium atom.įirst, let us determine the number of protons in the sodium atom.

Electronic configuration of sodium is 1s 22s 22p 63s 1.The above-shown sodium box provides us with the following information: Sodium is an alkali metal and belongs to the Group 1A of the periodic table: The electrons are distributed in K, L, and M shells around the nucleus. The sodium atom has 11 protons, 12 neutrons, and 11 electrons. These electrons take part in the formation of bonds between different atoms.

The electrons present in the outermost shell of the nucleus have maximum energy and are also known as valence electrons. The electrons jump to higher orbits after absorbing a certain amount of energy. with the lowest number being assigned to the shell located closest to the nucleus.Īs per the Bohr-Rutherford model, the shell positioned closest to the nucleus has minimum energy and the electrons residing in that shell are known to be in the ground state. The names of the shell are given as K, L, M, N, etc., or 1, 2, 3, 4, 5, etc. These are fixed tracks and the number of electrons that can be accommodated in a single shell also differs. Shell: The circular path taken by the electrons around the nucleus is known as shell or orbit.The Bohr-Rutherford model postulates that the electrons revolve around the nucleus in predetermined circular orbits. Electrons: These are the negatively charged species that revolve around the nucleus of the atom.They are also responsible for many physical properties of the atom. Neutrons: These are present in the nucleus along with protons and are responsible for the stability of an atom.They were named by Ernst Rutherford and are denoted by the symbol p +. Protons: These are the positively charged particles located in the nucleus of the atom.It is composed of positively charged protons and neutral neutrons. Nucleus: The positively charged body that lies at the center of the atom is known as the nucleus.The terms used in the Bohr atomic model are given below: To understand the Bohr model of the atom we must first recognize the atomic particles and their relevance in the atomic structure. It illustrates the number as well as the location of all the atomic species inside an atom. The Bohr model is a representation of the atomic structure along with all the atomic particles in pictorial form. The Bohr-Rutherford model was given in 1913 after incorporating the findings of Niel Bohr in the already given Bohr model.

Sodium atom