Final answer:
Elements form ions typically to reach a noble gas electron configuration. Group 17 elements gain 1 electron to form 1- anions, Group 13 elements lose 3 electrons to form 3+ cations, Group 1 elements lose 1 electron to form 1+ cations.
Step-by-step explanation:
When elements form ions, they can either lose or gain electrons to achieve a stable electronic configuration. The number of electrons lost or gained is dependent on the group of the element in the periodic table.
- F (fluorine) is a group 17 element and will gain 1 electron to achieve the configuration of a noble gas, forming a 1- anion.
- Group 3A (or Group 13) elements, like Al (aluminum), will lose 3 electrons to form a 3+ cation.
- Cs (caesium) is a group 1 element and will lose 1 electron to form a 1+ cation.
- I (iodine) is also a group 17 element and will gain 1 electron to form a 1- anion, similarly to fluorine.
- Al (aluminum), as previously mentioned, will lose 3 electrons to form a 3+ cation.
Remember that for main group elements, ions are formed by gaining or losing valence electrons to achieve the electron configuration of the nearest noble gas. Group 1 and 2 elements form cations by losing all of their valence electrons, aligning with the group number. For groups 13-17, the charge of the cation formed is equal to the group number minus 10 after losing all valence electrons.