Conduction can occur within a single substance but parts must have what property?

• A. Different textures
• B. Different particle sizes
• C. Different temperatures
• D. Different colors

Answer: (C)

Heat transfer by conduction requires a temperature gradient. Within a single substance, energy moves from regions that are hotter to regions that are cooler, so parts must have different temperatures. The hotter area has higher molecular energy and transfers some of that energy to neighboring parts through collisions and lattice vibrations; in metals, free electrons speed up this energy transfer. If all parts share the same temperature, there’s no net conduction. Other properties like texture, particle size, or color don’t create the driving force for conduction because they don’t establish a temperature difference.