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animalloverdomaille2

Answer: i know one of them,

Sodium and Lithium

Explanation: hope this helps have an awesome day! :)
the atomic number of magnesium is 12 so there would be 12 protons and 12 electrons. you would then have to round the atomic mass at the bottom up or down giving you the mass number. subtract the number of protons from the mass number to give you neutrons. there is 12 neutrons