Given a scientific question, generate a correct answer to it.
--------
Question: What is a hydrocarbon in which the carbon chain joins to itself in a ring?

Answer: cyclic hydrocarbon

Question: What process is involved in the formation of a waterfall, when a stream flows from an area of harder to softer rock?

Answer: erosion

Question: What corrosive substances capable of dissolving many metals can cause contamination if spilled?

Answer:
acids