Q. $MnO_{2}$ dissolves in water to give an acid. The colour of the acid is
A) Green
B) Blue
C) Violet
D) Red
Explanation
(c)
$Mn_{2}O_{7} + H_{2}O \rightarrow 2HMnO_{4}$
$HMnO_{4}$ is permanganic acid, which is violet in colour
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.