Which of the following is a characteristic of hazardous materials?

Hazardous materials are characterized by their ability to exist in multiple states of matter, specifically solids, liquids, and gases. This versatility is essential to understand as it influences how these materials are handled, stored, transported, and disposed of. Each form presents unique risks and requires specific measures to ensure safety and compliance with regulations.

In the case of the other options, stating that hazardous materials are always liquid is inaccurate, as many hazardous substances can indeed be in solid or gaseous form. The assertion that they have no regulations governing their transportation is also incorrect; in fact, hazardous materials are subject to strict regulations that dictate their handling and transportation to protect public health and the environment. Lastly, the claim that they are typically inexpensive to ship is misleading. Due to the risks associated with hazardous materials, shipping costs can often be higher because of the need for specialized packaging, labeling, handling procedures, and potentially increased insurance premiums. Overall, the defining characteristic of being able to exist in multiple physical states is critical in understanding the nature of hazardous materials and managing their risks effectively.