Question

Given below are two statements:
Statement (I) : Oxygen being the first member of group 16 exhibits only –2 oxidation state.
Statement (II) : Down the group 16 stability of +4 oxidation state decreases and +6 oxidation state increases.
In the light of the above statements, choose the most appropriate answer from the options given below:

• A. Statement I is correct but Statement II is incorrect
• B. Both Statement I and Statement II are correct
• C. Both Statement I and Statement II are incorrect
• D. Statement I is incorrect but Statement II is correct

Answer 1

Answer: (C)

Both Statement I and Statement II are incorrect

Answer 2

Statement I: Oxygen, as the first member of group 16, primarily exhibits an oxidation state of $-2$ due to its high electronegativity and small size, which favors electron gain rather than loss. However, it can also exist in oxidation states other than $-2$, such as 0 in molecular oxygen ($O_2$), and $+1$ or $+2$ in compounds like $OF_2$ and $O_2F_2$. Therefore, the statement that oxygen exhibits only a $-2$ oxidation state is incorrect.

Statement II: In group 16 elements, moving down the group from oxygen to polonium, there is an observed increase in the stability of the $+4$ oxidation state, while the stability of the $+6$ oxidation state decreases. This trend is attributed to the inert pair effect, where the tendency of the $s$-electrons to remain unpaired increases in heavier elements, making higher oxidation states less stable. Thus, elements like tellurium and polonium prefer to exhibit the $+4$ oxidation state rather than $+6$. Hence, the statement that the stability of the $+4$ oxidation state decreases down the group is also incorrect.

The Correct answer is: Both Statement I and Statement II are incorrect