What element in the second period has the largest atomic radius?

1 Answer
Mar 17, 2016

Answer:

Why, lithium.

Explanation:

We look at #Li#, #Z=3#, versus #Ne#, #Z=10#.

As scientists we should always consider the data . The atomic radius of #Li# #=# #167xx10^-12 m#; the atomic radius of #Ne# #=# #38xx10^-12 m#.

This is quite a stunning decrease in radius. Atomic radii decrease ACROSS the Period going from left to right due to increased NUCLEAR CHARGE. As #Z# increases sequentially, the effective nuclear charge increases as the electrons, adding to the same shell, shield each other VERY imperfectly, and atomic radii contract.