Folyadékfázis

Folyadékfázis is the Hungarian term for the liquid phase of matter, the state in which a substance has a definite volume but no fixed shape, taking the shape of its container. In the liquid state the atoms or molecules are less tightly packed than in solids, but still interact closely enough to resist significant flow under normal conditions. The cohesive forces that dominate the liquid phase are primarily intermolecular attractions such as hydrogen bonding, dipole–dipole interactions, and London dispersion forces.

The transition between the solid, liquid, and gaseous phases occurs at characteristic temperatures: melting occurs when solids become liquids; boiling is the conversion of liquids directly into gases. Heating a liquid increases molecular kinetic energy and reduces viscosity, while cooling a liquid raises viscosity and eventually leads to freezing. Pressure also influences phase transitions, as described by the phase diagram of a substance.

In practice, the liquid phase plays a vital role in numerous processes: it serves as a medium for chemical reactions, heat transfer, and the transport of nutrients. Liquids also exhibit bulk properties such as surface tension, capillarity, and compressibility, all of which arise from intermolecular forces. Understanding the behavior of liquids is essential in fields ranging from materials science and metallurgy to biology and environmental science.