"Name an atom with the same electron configuration as the Ca2+ ion and an atom with the electron configuration of an Ca+ ion. Which calcium ion of the two is the most stable? Is this an anion or a cation?" This is what i have been asked to answer and i know thatArgon has the same EC as Ca2+ and i think that potassium has the same as Ca+ but i not sure and i think that bth are anions. Any help at all would be great,thank you