Question

Consider following as a portion of the periodic table from Group no.13 to 17. Which of the following statement/s is/are true about the elements shown in it?

			V	Z
W				Y
X

A) V, W, Y, and Z are less electropositive than X.
B) V, W, X, and Y are more electronegative than Z.
C) Atomic size of Y is greater than that of W.
D) Atomic size of W is larger than that of X.

Answer 1

Hint: A tendency of an element to lose an electron and generate a positive ion is called the electropositive character. The electropositive character decreases along with the period and increases along with the group. It is inversely related to the ionization energy of an element.$\text{ Electropositive }\propto \text{ }\dfrac{1}{\text{Ionisation energy (IE)}}\text{ }$

Complete step by step answer:
A tendency of an element to lose electrons and form positive ions is known as the electropositive or metallic character. The electropositive character is inversely related to the ionization energy. Ionisation energy is the amount of energy required by an element to lose valence shell electrons. Lower the ionization energy of an element higher is the tendency of an element to lose an electron. Thus higher is the electropositive character. It is given as,$\text{ Electropositive }\propto \text{ }\dfrac{1}{\text{Ionisation energy (IE)}}\text{ }$
Alkali metals have the lowest ionization energy and thus they are highly electropositive elements. In a periodic table, along the period the ionization energy goes on increasing from left to right. In other words, the electropositive character of the elements goes on decreasing. Along with the group, the ionization energy of an element goes on increasing as we move from top to bottom. That is electropositive character increases as we from top to bottom in a group. Electronegativity is the opposite of the electropositive nature of the element. Along the period, electronegativity goes on increasing from left to right and decreases along with the group. If we consider a portion of the periodic table given to us, we will be able to make the following statements from it. Along with the group, atomic size increases from top to bottom thus X has a larger size than W. Along the period, electronegativity increases or electropositive character decreases from left to right. Thus, Z is more electronegative among all and X is more electropositive among all given elements. With respect to element X, elements V, W, Y, and Z are less electropositive.

Hence, (A) is the correct option

Note: Note that ionization energy depends on the size of the atom. The Larger the size of atoms, the less is the interaction between the nucleus and outermost electrons. Thus, such electrons can be easily knocked out from the elements. Thus ionisation energy is inversely related to the size of an atom. Therefore, in a periodic table $\text{ Cs }$ is a highly electropositive element. For electronegative elements the trend gets reversed. Thus Fluorine is a highly electronegative element.