Question #a157c

1 Answer
Feb 16, 2017

Answer:

#"Atomic size decreases across a Period............"#

Explanation:

Atomic size decreases across a Period, from left to right as we face the Table. Why? Because nuclear charge is VERY imperfectly shielded by partly filled electronic shells, and as the nuclear charge increases, the attractive pull on the valence electrons becomes GREATER. The result? A progressive decrease in atomic radii.

ck12.org

And you have boron, #Z=5#, versus oxygen, #Z=8#. The atomic radius of boron is #85xx10^-12*m#; that of oxygen is #60xx10^-12*m#. Are these data consistent with the above spray?