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Atom

 Hello! 


How are you all? Today our topic is Atom.  We all heard about atom. 

The smallest particle of an element is called atom. Atoms are the basic building blocks of matter. Anything that takes up space and anything with mass is made of atom. 

An atom is a particular of matter that uniquely defines a chemical element. An atom consist of a central nucleus that is surrounded by one or more relatively heavy particles known as proton and neutron. 

 

This was the short introduction of atom. Next we will discuss structure of atom. 



Structure of Atom:



The total mass of an atom, including the protons, neutrons and electrons, is the atomic mass or atomic weight. The atomic mass or weight is measured in atomic mass units.

Electrons contribute only a tiny part to the mass of the atomic structure, however, they play an important role in the chemical reactions that create molecules. The atomic weight can be thought of as the number of protons plus the number of neutrons. Because the number of neutrons in an atom can vary, there can be several different atomic weights for most elements. Protons and electrons have equal and opposite charges. Protons have a positive charge and electrons a negative charge. Normally, atoms have equal numbers of protons and electrons, giving them a neutral charge.


Proton:

A proton is positively charged. The number of protons in the nucleus of an atom is the atomic number for the chemical element. A proton has a rest mass, denoted mp of approximately 1.673 x 10-27 kilogram(kg). 


Electron:

An electron is a negatively charged subatomic particle. The negative charge is equal to 1.602 × 10-19 coulomb in magnitude. The mass of an electron is 1/1837 of a proton.


Neutron:

A neutron is electrically neutral and has a rest mass, denoted mn, of approximately 1.675 x 10-27.


See you soon. Thank you. 

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