what is the highest and lowest oxidation number of silver ?

Dear Student,

Electronic configuration of Ag=  [Kr] 4d¹⁰ 5s^​1
Here, Number of unpaired electrons = 1
So, common oxidation state of Ag is +1
It even shows +2 and +3 oxidation states
Therefore, Highest oxidation state of Ag = +3 while the lowest oxidation state of Ag = +1