CUET · CHEMISTRY · PYQ PAPER 2023
Which of the following statements are true regarding Lanthanoid elements?
i. \(\text{La}(\text{OH})_3\) is the basic hydroxide of Lanthanoids.
ii. \(\text{Zr}^{4+}\) and \(\text{Hf}^{4+}\) ions have almost similar ionic sizes.
iii. \(\text{Ce}^{4+}\) acts as an oxidising agent.
iv. Trivalent Lanthanoid ions are not coloured.
Choose the correct answer from the options given below:
- A (i) and (iii)
- B (iv) and (i)
- C (ii) and (iii)
- D (ii) and (iv)
Answer & Solution
Correct Answer
(C) (ii) and (iii)
Step-by-step Solution
Detailed explanation
ii. True. iii. True. The correct option is (ii) and (iii).
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