posted by Kaleen P .
It asks:For each of the following atomic numbers, use the periodic table to write the formula (including the charge) for the simple ion that the element is most likely to form in ionic compounds. For example, they gave 56, and the answer is Ba(2+), but I don't understand how you are to figure that out...
Get a periodic chart. There are many numbers on the chart and the one you want to find is the atomic number. That's the ONLY number on the chart that increases by 1 from an element to the next element. For example, H is 1, He is 2, Li is 3, Be is 4, B is 5, C is 6 etc. When the problem give you an atomic number you simply find that number on the chart and that's the element. For 56 that is Ba. You write the charge from the column. Column 1 would be A^+, column (a in Ba) is Ba^2+, column 3 is A^3+ (Al is an example). V, VI, and VII are -3, -2, ad -1. Etc.