To determine which two elements would bond together based on their ionic charges, we need to look at their positions in the periodic table and their common ionic charges:
- Potassium (K) is in Group IA (1A) and typically has a +1 charge when it forms an ion (K⁺).
- Calcium (Ca) is in Group IIA (2A) and typically has a +2 charge when it forms an ion (Ca²⁺).
- Iodine (I) is in Group VIIA (7A) and typically has a -1 charge when it forms an ion (I⁻).
- Neon (Ne) is in Group VIIIA (8A) and is a noble gas, so it does not readily form ions.
Based on this information, we can see that Potassium (K⁺) and Iodine (I⁻) would bond together to form the ionic compound potassium iodide (KI). The charges balance out (+1 from potassium and -1 from iodine).
Therefore, the correct response is:
potassium and iodine.