J.J. Thomson made the groundbreaking discovery of electrons in 1897.
- According to J. Thomson’s experiments with cathode ray tubes, all atoms contain tiny negatively charged subatomic particles or electrons, which are known as electrons.
- He carried out an experiment on cathode rays and discovered that they are charged particles by the results.
- When compared to the speed of light, the velocity of cathode rays was significantly slower.
- As a result, he devised novel methods for measuring the charge to mass ratio of cathode rays.
- Thompson concluded as a result that cathode rays are the 11000th mass of hydrogen ions in the universe (which is a proton). The electrons, which are negatively charged cathode ray particles with negligible mass, were named after the negatively charged cathode ray particles.
Discovery of proton:
Physicist E. Goldstein demonstrated the presence of proton atoms in atoms in 1886.
Streams of heavy particles were released by the anode when Goldstein passed electricity at high voltage through a gas at very low pressure that was placed in a discharge tube (positive electrode).
- Anode rays are a term used to describe these streams of particles.
- Protons make up the anode rays emitted by hydrogen cells as they decay.
- When we remove an electron from the hydrogen atom, we can produce a proton as a result.
H (hydrogen atom) = H+ (proton) + e-(Electron).
- As a result, the proton is a hydrogen ion (H+).
- The charge to mass ratio of positive particles is found to be dependent on the nature of the gas present in the discharge tube, according to his findings.
- As a result, the charge to mass ratio (e/m) varied depending on the gas being studied.
- In the case of hydrogen gas, it was the highest, primarily because hydrogen is the lightest atom, meaning that m will be the least, and thus the e/m ratio will be the highest in this case.
- Every element contains a proton, which is a positively charged particle found in the atoms of each element.
- Protons are found within the neutron.
Characteristics of proton:
- Protons Relative Mass: The proton’s relative mass is one unit of mass.
- In the same way that an electron has an opposite charge to a proton, a proton also has an equal and opposite charge. A proton has an absolute charge of 1.6 x 10-19 coulomb of positive charge, which is a very small amount.
Discovery of neutron:
The discovery of another subatomic particle by James Chadwick in 1932 was a watershed moment in science.
The neutron is the name given to this particle.
Atoms contain neutrons, which are neutral particles that are found in their nuclei.
Characteristics of neutron:
Neutron’s Relative Mass: The neutron’s relative mass is one unit of mass.
An electron has no charge, and a neutron possesses none.
Finding atomic number and number of proton, neutron and electron:
Atomic number: It is simply the number of protons in an element’s nucleus that determines the element’s atomic number. The simplest method of determining the atomic number is to consult a periodic table; the atomic number is located in the upper left corner of the table or is the largest number on the square.
Number of protons: Atoms have a number of protons equal to the atomic number of the element in which they reside. Take, for example, the element oxygen. The atomic number of oxygen is eight in the periodic table, according to science. The atomic number of an element is located above the symbol of the element. Due to the fact that oxygen has an atomic number of eight, there must be a total of eight protons in the compound. Furthermore, the number of protons in an element remains constant throughout its lifetime.
Number of neutrons: It is possible to calculate the number of neutrons present in an atom by subtracting the atomic number from the atomic mass. Both of these numbers can be found on the periodic table, which you can see here. The atomic number of an element is listed above the symbol of the element, whereas the mass number of the element is listed below the symbol. Let us continue to use the element oxygen as an example. It has an atomic mass of 15.999 atomic mass units (amu) and an atomic number of 8. Its atomic mass is measured in atomic mass units (amu). In this case, we will get 8 when we subtract 8 from 15.999. It should also be noted that the number of neutrons in an element can vary depending on its composition. It is possible for some elements to have isotopes with different masses and, as a result, different numbers of neutrons than one another.
Number of electrons: For neutrally charged species, the number of electrons in an atom is equal to the atomic number of the element in which it exists. This means that the number of electrons in an element and the number of protons in an element are the same as one another. As a result, the number of electrons present in oxygen is eight. Furthermore, because the charges of these two subatomic particles, electrons and protons, are diametrically opposed, they cancel each other out and maintain the atom’s neutrality.
Conclusion:
J.J. Thomson, E. Goldstein and James Chadwick, all three scientists had a major role in chemistry by discovering the Electrons, Protons and Neutrons.
J.J. Thomson made the groundbreaking discovery of electrons in 1897.
Physicist E. Goldstein demonstrated the presence of proton atoms in atoms in 1886.
Streams of heavy particles were released by the anode when Goldstein passed electricity at high voltage through a gas at very low pressure that was placed in a discharge tube.
The discovery of another subatomic particle by James Chadwick in 1932 was a watershed moment in science. It is simply the number of protons in an element’s nucleus that determines the element’s atomic number.