Question

Which of the following statements are correct concerning redox properties?

(i) A metal M for which $E^{\circ }$for the half cell reaction $M^{n+}+n{e}^{-}\rightleftharpoons M$ is very negative and will be a good reducing agent

(ii) The oxidizing power of the halogens decreases from chlorine to iodine

(iii) The reducing power of hydrogen halides increases from hydrogen chloride to hydrogen iodide

• A. (i), (ii) and (iii)
• B. (i) and (ii)
• C. (i) only
• D. (ii) and (iii) only

Answer 1

The correct option is A (i), (ii) and (iii)

Explanation :

(i) High – ve $E^{\circ }$ value means lower reduction potential which means, the metal M is a good reducing agent.

(ii) Reduction potential of Cl, Br and I are respectively: + 1.36 V, 1.06 V and 0.54 V. Higher reduction potential means, good oxidising agent. Thus, oxidising power decreases from $Cl\to Br\to I$

(iii) Larger the size of halogen atom, weaker the bond and easier is the tendency to given hydrogen. Thus, stronger is the reducing power. As size of halogen $Cl<Br<I$ , thus, the reducing power of $HCl<HBr<Hl$