JEE MainChemistryd and f Block Elements
Given below are two statements: Statement I: KMnO ₄ oxidizes iodide to iodate in faintly alkaline medium, whereas in acidic medium it oxidizes iodide to iodine. Statement II: K ₂ Cr ₂ O ₇ oxidizes iodide to iodate and hydrogen sulfide to sulfur in acidic medium. In the light of the above statements, choose the most appropriate answer from the options given below:
Options
- AStatement I is true but Statement II is false
- BBoth Statement I and Statement II are true
- CBoth Statement I and Statement II are false
- DStatement I is false but Statement II is true
Correct answer
A. Statement I is true but Statement II is false
Step-by-step solution
Statement I is true. In faintly alkaline or neutral medium, KMnO ₄ oxidizes iodide ( I ^- ) to iodate ( IO ₃^- ). In acidic medium, KMnO ₄ oxidizes iodide to iodine ( I ₂ ). Statement II is false. In acidic medium, K ₂ Cr ₂ O ₇ oxidizes hydrogen sulfide ( H ₂ S ) to sulfur ( S ), but it oxidizes iodide ( I ^- ) to iodine ( I ₂ ), not to iodate ( IO ₃^- ). Therefore, Statement I is true but Statement II is false. Answer: Statement I is true but Statement II is false