Question

Consider the following statements

I. $La(OH)_{3}$ is least basic among hydroxides of lanthanides

II. $Zr^{4 +}$ and $Hf^{4 +}$ possess almost the same ionic radii.

III. $Ce^{4 +}$ can act as an oxidizing agent.

Which of the above is/are true?

• A. I and III
• B. II and III
• C. II only
• D. I and II

Answer 1

Answer: (B)

II and III

Answer 2

$La(OH)_{3}$ is most basic, hence (I) is wrong. (II) is correct due to lanthanoid contraction. (III)is correct because $Ce^{4 +}$tends to change to stable $Cr^{3 +}$