Sunday
May 1, 2016

# Homework Help: chemistry

Posted by Fidelia on Tuesday, January 23, 2007 at 5:45pm.

How many electrons would Nitrogen, Aluminum, and Bromine gain or lose?

Look at the periodic table and find N, Al, and Br.
You should find N in group VA (or 15 depending on the system being used), Al in IIIA (or 13), and Br in VIIA (or 17). I will show you in detail how to do a couple.
Al is in group IIIA so it has 3 electrons in its outer shell. That means it will lose those 3 (or gain 5 but losing 3 is much easier, wouldn't you think?). If it loses those 3 electrons it will form the Al^+3 ion.

Br is in group VIIA. It has 7 electrons in its outer shell. (Note Al is in IIIA or 13 and had 3. Br is in VIIA or 17 and has 7---do you see how just by looking at the periodic table you can tell how many electrons are in the outer shell?). So Br would be expected to lose 7 or gain 1. Of course, gaining 1 is the easier and it does that to become a Br^-1 ion.

N is in group VA or 15. How many electrons are in the outer shell? So how many electrons can it gain or lose? Actually, it can do both.

Oh, okay, thanks for the great explanation. I understand now.