Subatomic Particles - Protons

Chemistry

definition

Discovery of proton by Goldstein

In 1886, E. Goldstein carried out discharge tube experiments and discovered new radiations and called them canal rays. These rays were made up of positively charged particles and led to the discovery of proton.

definition

Canal Rays

A canal ray (also positive ray or anode ray) is a beam of positive ions that is created by certain types of gas dicharge tubes.

definition

Define proton and explain its properties

A proton is a subatomic particle , symbol p or p+, with a positive electric charge of +1 and mass slightly less than that of a neutron present in nucleus of every atom. The number of protons in the nucleus is the defining property of an element, and is referred to as the atomic number (represented by the symbol Z).
properties :
ParticleChargeMass (g)
Proton+11.6727 x 10-24

definition

Postulates of discovery of protons

The actual mass of proton is 1.672 gram.Proton has mass of 1.00727 atomic mass unit.
Since proton was the lightest positive particle found in atomic beams, found in the discharge tube , it was thought to be present in all other atoms.

definition

Properties of anode rays

Some of the characteristic properties of anode rays are:

  1. Anode rays consist of material particles.
  2. Anode rays are deflected by electric field towards negatively charged plate. This indicates that they are positively charged.
  3. The charge to mass ratio of the particles in the anode rays was determined by W. Wien by using Thomsons technique. Charge to mass ratio of the particles in the anode rays depends upon nature of the gas taken in the discharged tube.
  4. They travel in straight line.

definition

Properties of Protons

Electrical discharge carried out in modified cathode ray tube led to the discovery of particles carrying positive charge, also known as 'Canal Rays'. The smallest and lightest positive ion obtained from Hydrogen was called 'proton'. It was first characterized in 1919. Results of these experiments shed some light on physical
properties of protons which are summarized below:
1. Behavior of these particles in magnetic and electric field is opposite to that observed for electron or cathode rays. Hence, they carry a positive charge as opposed to negative charge on electrons.
2. The charge to mass ratio is lower than that of electrons. 

REVISE WITH CONCEPTS

Subatomic Particles - Electron

ExampleDefinitionsFormulaes

Subatomic Particles - Neutrons

ExampleDefinitionsFormulaes

Atomic Theory of Matter

ExampleDefinitionsFormulaes
LEARN WITH VIDEOS
Important Questions
View solution
>
View solution
>
View solution
>
View solution
>
View solution
>
View solution
>
View solution
>
View solution
>
View solution
>
View solution
>