Answer:
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Step-by-step explanation:
Remember that protons have a positive charge of +1 and electrons have a negative charge of -1. Atoms have protons and electrons.
A sodium atom has the electron configuration of 2-8-1. It has 11 electrons and its atomic number (number of protons) is also 11. This means it is a neutral atom because the charges of the electrons (-11) and protons (+11) balance each other out.
However, a sodium ion is different. It loses the 1 valence electron, so it only has 10 electrons. It still has the same atomic number of 11.
It is a not a neutral atom because the charges of the electrons (-10) and protons (+11) do not balance out. It has more protons and a net positive charge of +1. It is a cation or a positively charged ion.