Iron rusts quickly in

A. Rain water

B. Sea water

C. Distilled water

D. River water

Answer: Option B

Solution(By Examveda Team)

Water is the enabler of fast oxidation of iron. So freshwater will also cause rust. However, salt water (sea water) is a very good conductor (lots of dissociated ions) and so there are a number of electrolysis reactions that tremendously accelerate corrosion in salt water. This effect can be reversed by using a metal (like zinc) which causes the current to be reversed and in effect the zinc corrodes rapidly, protecting the iron.