This answer is
not correct. Since silicon is in the same period as phosphorus, the distance of
the outer electrons from the nucleus is close and the number of protons in the
nucleus is one less than phosphorus. Electronegativity increases from left to
right in a period because the number of protons in the nucleus is increasing and
the distance of the outer electrons from the nucleus is relatively
similar...although the diameter is decreasing because of electronegativity.