All phosphorus atoms have 15 protons (hence their atomic number of fifteen). Assuming the atom is neutral, it will also have an equal amount of electrons.
A neutral atom of phosphorus has 15 protons, 15 neutrons, and 15 electrons. Each proton has a positive charge, each neutron has no charge, and each electron has a negative charge, resulting in the atom being electrically neutral.
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An atom of chlorine has 17 protons.
The atom must have 8 electrons to make it have a neutral charge
protons
If a neutral atom of sodium has 11 protons, it will have 11 electrons also.
A neutral atom with 12 protons will have 12 electrons in order to balance the positive charge from the protons.
8 protons
There are 6 protons in a neutral atom of Carbon 13
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