Question

The electropositive character across a period ________ while electronegative character down a group _______.
A.Increases, decreases
B.Decreases, increases
C.Increases, increases
D.Decreases, decreases

Answer 1

Hint: we must understand that the smaller the size of atom higher the electronegativity and larger the size of atom higher the electropositivity.

Complete step to step solution:
When an atom tends to lose their electrons, they form positive ions and this is called electropositivity. You must keep in mind that electropositivity is directly proportional to the metallic character of an atom. That is why, the more electropositive an atom is, the more metallic character it shows.
In this case, as we move across the period, the nuclear charge increases. This causes a decrease in the atomic size because the nucleus attracts the electrons towards itself. As the nuclear charge is also high, and the size is also small, it becomes very difficult to remove the valence electrons from the valence shell due to strong attractive forces. If an atom cannot lose electrons easily, their electropositive nature is less and hence as we move across a period electropositivity decreases and its electronegativity increases.
Electronegativity, on the other hand, is the tendency to gain electrons and form negative ions. The more electronegative an atom is, the more non-metallic characters it shows.
Also, as we move down a group, the size (atomic radius) of the atom increases. This is due to an increase in the number of shells and an increase in the shielding effect. There is less attraction between the nucleus and the valence electrons due to this and valence electrons are easily lost. That is why as we move down a group, the electronegativity of an atom decreases and the electropositivity of an atom increases.

So, we can conclude that the answer to this question is D. because the electropositive character across a period decreases while electronegative character down a group decreases.

Note: Always remember, that as we move down the period the electropositivity and electronegativity of the atom increases and decreases respectively. On the other hand, when we move across the period the electropositivity and electronegativity of the atom decreases and increases respectively.