When lycopodium powder is spread on the surface of clean water, it typically tends to form a thin, floating layer rather than dissolving. This occurs because lycopodium powder is hydrophobic, meaning that it does not mix well with water and repels it.
As a result, the powder can create interesting visual effects, such as the formation of patterns or films on the water surface. Additionally, if disturbed, the lycopodium powder can create small clouds of fine particles, which can float momentarily before settling. This behavior is often used in demonstrations to illustrate concepts of surface tension and hydrophobicity.