Which of the following is an example of a non-porous surface?

A non-porous surface is characterized by its impermeability, meaning it does not allow liquids or gases to pass through it. In this case, glass is a prime example of a non-porous material because it is solid and smooth, lacking any pores or openings where substances could infiltrate or be absorbed.

In contrast, materials such as cardboard, paper, and raw wood are porous. Cardboard and paper can absorb liquids due to their fibrous nature, allowing moisture or other substances to permeate them. Raw wood, while solid, has natural pores and fibers that can absorb liquids, making it porous as well. Recognizing the differences among these materials is essential, especially in contexts such as crime scene investigations or hazardous material handling, where the properties of these surfaces can significantly impact evidence collection and preservation.