Question

13) Which statement is true about effective nuclear charge? A) effective nuclear charge increases as you move to the right across a row in the periodic table and increases as you move down a column. B) effective nuclear charge increases as you move to the right across a row in the periodic table and decreases as you move down a column. c) effective nuclear charge decreases as you move to the right across a row in the periodic table and decreases as you move down a column. D) effective nuclear charge decreases as you move to the right across a row in the periodic table and increases as you move down a column. E) none of these 14) Which of the elements listed below has the greatest atomic radius? A) B Β) ΑΙ C) S D) P E) Si 15) How many unpaired electrons does a ground-state atom of sulfur have? Hint: Draw the orbital notation diagram. B) 1 D) 3 E) 4 A) O C) 2

Answer 1

Q13. Nuclear Charge is the attractive positive charge of protons acting on valence electrons.

The nuclear charge increases across the period because if we move left to right in a period the atomic number increases and thus, it increases nuclear charge.

Also, if we move down the group the atomic number increases but due to shielding effect the nuclear charge decreases.

The shielding effect can be defined as a decrease in the nuclear charge on the electron cloud, due to a difference in the attraction forces on the electrons in a particular atom.

Thus,option B is the correct answer.