Q: When calcium metal reacts with sulphuric acid, the reaction stops after a short while. Why?
(a)The reaction of calcium with sulphuric acid is not feasible at room temperature
(b)Formed calcium sulphate is insoluble in water and covers the calcium metal, preventing it from reacting any further
(c)Formed calcium sulphate requires two molecules of water to crystallize as gypsum
(d)Formed calcium sulphate is unstable
Correct Answer: (b)
The correct answer is (b): Formed calcium sulphate is insoluble in water and covers the calcium metal, preventing it from reacting any further. Subject: Geography | Sub-topic: Atmosphere & Climatology