Question

Consider the following statements
I. The radius of an anion is larger than that of
the parent atom.
II. The ionization energy generally increases
with increasing atomic number in a period.
III. The electronegativity of elements increases
on moving down across a group.
Which of the above statements is/are correct?
(a) I alone (b) II alone
(c) I and II (d) II and III

Answer 1

Answer:

c is the correct answer

Answer 2

(c) I and II

Explanation:

The correct statements are:

I. The radii of an anion is larger than that of the parent atom. The parent atom is neutral and have same number of protons and neutrons. But in an anion, the electrons are more in number than the number of protons, so effective nuclear charge of anion is less. The size of the anion is larger than that of the parent atom.

II. The ionization energy generally increases with increasing atomic number in a period. As we go from left to right in a period, the atomic size decreases due to increase in the atomic number, leading to increase in effective nuclear charge. So the ease of releasing the electrons becomes lesser, and the ionisation energy required to remove the electrons increases from left to right in a period.

Option C is the answer.