JAMB - Chemistry (2023 - No. 56)
When anhydrous cobalt chloride paper is exposed to water, what color change is observed?
From pink to blue
From white to blue
From blue to white
From blue to pink
Explanation
nhydrous cobalt chloride paper is blue in the absence of water. However, when it comes into contact with water, it undergoes a color change to pink due to the formation of hydrated cobalt chloride.