Question

Using the periodic table, determine the ion charges of the following elements if valence electrons were removed or added to reach the octet.
Barium:
Iodine:
potassium:
aluminum:

Answer 1

Please help!!

Answer 2

Barium:2+
iodine: 1-
potassium: 1+
aluminium: 3+

Remember which group this element they come from and you roughly can know which charge.

when you add electron to reach octet, the charge becomes more negative. Let say you add one electron to iodine, iodine (charge=0) become iodide(charge=-1). If you remove one electron to reach octet, the charge becomes more positive. Example: remove valence electron of potassium will make the charge to change from 0 to +1.

i hope this helps. Correct me if i'm wrong.