Which of the following has the largest effective nuclear charge?
A) Al
B) Si
C) P
D) S
E) Cl

Question

Quizplus · Accepted Answer

Effective nuclear charge increases as you move across a period from left to right. This is because the number of protons in the nucleus increases, but the shielding effect of inner electrons remains constant. Therefore, the element with the highest atomic number in the group is expected to have the highest effective nuclear charge. Among the given elements, Cl has the highest atomic number, and hence the highest effective nuclear charge.

Which of the Following Has the Largest Effective Nuclear Charge