SO3 is not absorbed in water directly to form sulfuric acid because
A. Reaction doesn't go to completion
B. Reaction is slow.
C. Highly exothermic.
The Attempt at a Solution
MY understanding: Because it results in the formation of mist or acid particles in air which does not condense easily.
From this I conclude that the answer is either C or D because the reaction does occur even though we don't get the product in the desired state and formation of mist doesn't seem slow to me...
Can anyone please clarify?