Suppose you are trying to find the identity of an unknown pure substance. The valence electrons of the substance's atoms feel an effective nuclear charge of + 1. If this substance's atoms have larger radii than potassium (K) atoms, what other characteristics would you expect the substance to exhibit?

A

It would have higher ionization energies than K and a higher electronegativity value than K.

B

It would have higher ionization energies than K and a lower electronegativity value than K.

C

It would have lower ionization energies than K and a higher electronegativity value than K.

D

It would have lower ionization energies than K and a lower electronegativity value than K.

Answer: Correct option is (D).

Explanation:

Given that unknown element has larger atomic radii than potassium atoms and its valence electrons feel an effective nuclear charge of + 1 which means that this unknown element belongs to group (I) of the periodic table.

In periodic table:

As we move down the group the value of ionization energy decreases down the group. This is due to increase in the size of an element. With increase in size valence electrons gets far away from the nucleus by which less energy will require to ionize the element. Electronegative characters also decreases when we move down the group. This is due to increase in size of an element by which electrons present in valence shells are far away from the nucleus.

So, It would have lower ionization energies than K and a lower electronegativity value than K.