posted by sel .
Which of the following elements is most likely to form an ion that will then form an ionic bond with an ion of a Group 1A element?
Fr **my choice
Iodine is the only non-metal there, it takes a non metal to form an ionic bond with a group 1 metal.
Quick Answer: "I"
Explanation: Since you're forming an iconic bond, you want to get the total valance electrons to 8.
Elements under 1A all have 1 valance electron, so all you really need to do is find an element with 7 electrons which under VIIIA column(7th column). The only elements in that 7th column are F, Cl, Br, I, and At. Therefore, I is the correct answer in this situation.
Hopefully this helps you out! I tried my best to explain how I got the answer.