|
|
Discovery of electron:–[br][br]An electron is a sub-atomic particle that carries a negative charge . In an atom, electrons travel around its nucleus that is made up of protons and neutrons. Protons are at a set distance from the nucleus because of the energy of the nucleus. That is why the orbit of the electrons is called the shell of the atom. The number of electrons determines the behavior of an atom. If the outermost shell is full, the atom is unreactive, i.e., it can neither share its electrons with other atoms nor take any electron from them. But if this shell is not full, it can lose/gain electrons to/from other atoms. The electron was discovered in 1895 by a british physicist, Joseph John Thomson. He was investigating the rays produced when an electric current passed through a vacuum. He found that the rays consisted of very small particles with negative charge. He named them electrons and later on proved that they were found in every atom.[br][br]
[br]Third party image reference[br]Discovery of proton:–[br][br] A proton is a sub-atomic particle in the nucleus of an atom. It is positively charged. Protons are slightly lighter than neutrons but about 2000 times heavier than electrons. The mukt a hydrogen atom has only one proton. Positive charge of the protons keeps constantly attracting the negatively charged electrons. The number of protons in an an atom of an element is called the atomic number of that element. A proton is made up of fundamental particles called quarks. The proton was first observed by a German physicist, Wilhelm Wien in 1902. But it was clearly discovered by a British physicist, J.J. Thomson in 1906 AD. Originally, it was believed that protons didn't break down. But during 1970s it came to be proved that protons can decay/break down into fundamental particles. These very particles are called quarks.[br][br]
[br]Third party image reference[br]Discovery of neutron:–[br][br]The neutron is a kind of particle that makes up the nucleus of an atom along with another kind of particle–proton. The neutron resembles the proton but it carries no charge– neither negative nor positive, and hence its name. It is, indeed, very difficult to detect the neutrons because they don't react at all. Atoms may differ in the number of neutrons even if they have the same number of protons. Such atoms are given the name–isotopes. The electron was discovered in 1932 AD by James Chadwick, a British physicist. Neutrons are very important in the production of nuclear energy as they are observed by the nuclei of some atoms and they cause them to split into two. Remember that hydrogen atoms have no neutrons in them at all. James Chadwick produced neutrons by using radiation from radioactive isotopes in order to bombard other atoms. He was awarded the nobel prize for physics in 1935.[br][br]
[br]Third party image reference[br][br]Please like, comment and follow, sources: (WORLDPHYSICS) Have a nice day! |
|
发表于 2019-06-02 04:28:43
收藏
Like
Stick Card
Jack
