Table of Contents
Why is the mass of an atom found mainly in nucleus?
13 Answers. The mass of an atom is found mainly in the nucleus because the atom has 3 subatomic particles in it. Protons, Electrons and Neutrons and the nucleus has Protons and Neutrons in it. Protons and Neutrons both have a mass of 1 atomic mass unit, where as electrons are so small they have basically no mass.
What is the nucleus made up of?
The nucleus is the tiny, dense, central core of the atom and is composed of protons and neutrons. Rutherford’s atomic model became known as the nuclear model. In the nuclear atom, the protons and neutrons, which comprise nearly all of the mass of the atom, are located in the nucleus at the center of the atom.
What is the difference between a nucleus and an electron?
The nucleus consists of neutrons and protons. One neutron or proton is about 1840 times bigger than an electron, which explains the difference of mass between nucleus and the elecrons. When Atomic Mass is calculated, the mass of the electrons is discounted, due to its relatively insignificant mass.
What is the difference between the atomic number and atomic mass?
Atomic number is the number of protons in the nucleus. Since this also determines the number of electrons a neutral atom has, the atomic number indicates the chemical element. In other words, all atoms with the same atomic number are the same chemical element. The atomic mass is, generally speaking, the sum of neutrons and protons in the nucleus.
What does the mass defect of a nucleus represent?
The mass defect of a nucleus represents the mass of the energy binding the nucleus, and is the difference between the mass of a nucleus and the sum of the masses of the nucleons of which it is composed. From this picture we see that most of the mass of the atom is located within nucleus.
What is the mass of an electron?
A proton and a neutron are both assumed to have a mass of 1 u, while an electron has a mass of 1 1836 u, so a lot of teachers would say that the mass of an electron is close to nothing or 0 u.