What is a caustic substance capable of doing?

A caustic substance is known for its ability to "eat away" or corrode materials through a chemical process. This characteristic is due to its reactive properties, which can break down the chemical bonds within different substances, leading to degradation or destruction. Caustic chemicals often include strong bases, such as sodium hydroxide, that can react vigorously with various materials, including metals and organic compounds.

While burning through plastics may happen due to the corrosive action of some caustic substances, not all caustics react with plastics in this way, making it less encompassing than the broader definition of eating away at materials through chemical means. The idea of heating rapidly when mixed with water is more relevant to certain compounds rather than being a defining property of caustics in general. Additionally, a frost-like effect typically refers to cryogenic substances or those that can create low temperatures but doesn't relate directly to the chemical corrosiveness associated with caustic materials. Therefore, the correct answer effectively encapsulates the primary and defining action of caustic substances.