118 Elements and Their Symbols and Atomic Numbers: Definition, Symbol with Atomic Number
The periodic table is a well-organized chart that contains all the known elements in the universe. These elements are ...
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Atomic number and mass number
For example, the atomic number of sodium is 11. Every sodium atom has 11 protons and 11 electrons. It has 11 positive charges and 11 negative charges. The mass number of an atom is its total ...