How many moles are 5.55 x 102 atoms of mg?
m2) an> nu x 02.0

Explanation:

number of atoms = moles × avegadro number

so 5.55 × 10^2 = moles × 6.023 × 10^23

moles = 5.55 × 10^2 ÷ 6.023 × 10^23 = 9.214×10−22 moles

they it depends on if one believes about radioactivity, they make a geiger counter beep but maybe it was going to beep anyway electronics do wierd things all the time or it was programmed to beep near certain metals.

atomic mass = 39

number of neutrons = 20

number of protons= 19

electronic configuration = 1s2 2s2 2p6 3s2 3p6 4s1

the number of electron in first shell = 2

number of electrons in n=3 shell = 8