Atomic Number and Mass Number
1. Define Mass Number.
Mass number is determined by the number of protons and neutrons combined inside the nucleus of the atom. It is represented by the symbol A.
- Mass Number (A) = Number of Protons + Number of Neutrons
2. How to find Mass Number of an Element?
Mass Number can be obtained by adding the total number of protons and neutrons present in the nucleus of an atom.
3. Why are Mass Numbers Whole Numbers?
Atomic Number and Mass number represent the number of sub-atomic particles that are present inside an atom and as we know that subatomic particles are not present in fractions but are rather always in whole numbers i.e. 1/2 electrons, 2/3 protons, etc do not exist. Thus, atomic numbers and mass numbers are always whole numbers.
4. What is Difference between Atomic Number and Mass Number?
The atomic number is the number of protons present in an atom while the mass number is the number of protons and neutrons present in an atom.
5. What is Mass Number of Sodium?
The mass number of Sodium is 23.
6. What is Mass Number of Oxygen?
The mass number of Oxygen is 16.
Mass Number
Mass Number of an atom is the total number of protons and neutrons present in an atom. We know that an atom consists of electrons, protons, and neutrons but the mass of the atom is contributed by protons and neutrons as the mass of electrons is very low hence it doesn’t contribute to the mass of an atom. In this article, we will learn what is the mass number, the mass number definition, the mass number formula, and the mass number of some commonly known elements.