Sagot :
Answer: The number of electrons in Cu^+ ion is 28.
Explanation: Copper has atomic number of 29 which means it has 29 electrons and 29 protons.
Argon is the noble gas with 18 electrons.
[tex]Cu(29 -[Ar]3d^{10}4s^1[/tex]
When Cu lose one electron it forms [tex]Cu^+[/tex] as now the number of protons are greater than the number of electrons.
The configuration of [tex]Cu^+[/tex] becomes [tex][Ar]3d^{10}[/tex]