What is a common characteristic of colloidal particles?

Colloidal particles are typically small enough that they remain evenly dispersed throughout a solution, which means they do not settle out quickly due to gravity. This property is a defining characteristic of colloids. The particles are generally within the size range of 1 nanometer to 1 micrometer, allowing them to stay suspended in a liquid or gas, preventing them from aggregating or separating under normal conditions.

The stability of colloidal systems is often attributed to the interactions between particles, which are maintained through various interactions like Brownian motion or electrostatic repulsion. This characteristic distinguishes colloids from solutions with larger particles, which tend to settle or can be filtered out more easily.

In contrast, the other options describe characteristics that do not apply to colloidal particles. For instance, colloidal particles are typically not visible to the naked eye, meaning they do not possess the visual clarity associated with larger particles. Furthermore, while some particles can pass through filter paper, many colloids are specifically defined by their ability to remain distributed in a medium without separation.