Question

The incorrect statement among the following is :-

• A. $VOSO _{4}$ is a reducing agent
• B. $Cr _{2} O _{3}$ is an amphoteric oxide
• C. $RuO _{4}$ is an oxidizing agent
• D. Red colour of ruby is due to the presence of $Co ^{3+}$

Answer 1

Answer: (D)

(i) In $VOSO _{4},{ }^{\prime} V ^{\prime}$ is in +4 oxidation state. So it act as oxidising agent.

(ii) $Cr _{2} O _{3}$ is an amphoteric oxide.

(iii) In $RuO _{4}$, 'Ru' is in +8 oxidation state. So it act as oxidising agent.

(iv) Red colour of ruby is due to the presence of $Cr ^{+3}$ ions in $Al _{2} O _{3}$.