Question

Successive ionization energies of an element X are 737.7 kJ/mole, 1450.7 kJ/mole, 10,500 kJ/mole respectively. What is the formula of the compound formed when it combines with a non-metal Y which has maximum number of unpaired electrons?

• A. $X{Y}_2$
• B. $X_2{Y}_3$
• C. $X_3{Y}_2$
• D. $X_{2}Y$

Answer 1

The correct option is C $X_3{Y}_2$

The third IE is very high as compared to second IE. Thus the element achieves inert gas configuration after losing $2$ electrons. Thus its valency is $2$. Y is non metallic and has maximum unpaired electrons, thus its valency is $3$. Hence X and Y from the compound $X_3{Y}_2$