Question

Which amongst the following has largest size?
a) Al
b) Al3+
c) Cl
d)Cl-​

Answer 1

Answer:

a) Al

Explanation:

Electronic Configuration of Cl is 2,8,7 and of Al is 2,8,3

Both have the same no. of shells and as Cl has more electrons in valence shell than Al, the charge is more which pulls the electrons closer towards the nucleus.

So, Al atom is larger than Cl atom and consequently larger than Cl- as well.

Now, Al3+ has lost all three valence electrons and has thus no electrons forming a third shell. Because of this, it has only 2 shells and is smaller than Al.