Chemistry
Define the terms : atomic number, mass number and electron.
Atomic Structure
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Answer
Atomic number [Z] of an element is the number of :
- Protons - in the nucleus of an atom
- Electrons - in the complete atom
- Positive charges - in the nucleus of it's atom
Mass number [A] of an atom is the total number of protons and neutrons in the atom of an element.
Electron [e] is a subatomic particle revolving around the nucleus of atom having unit negative charge 1.602 x 10-19 coulombs, and mass of 9.107 x 10-28 g. It is 1⁄1837 of the mass of a hydrogen atom or proton.
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