Kapaliny

Kapaliny are one of the fundamental states of matter in physics and chemistry. They have a definite volume but take the shape of their container, allowing them to flow. Compared with solids, the particles in liquids are less tightly bound, which gives rise to properties such as viscosity and diffusion. Liquids are relatively incompressible and exhibit surface tension and capillary action at interfaces with other substances.

Physical properties of liquids vary widely. Density ranges from well below 1 g/cm³ to above 1.5 g/cm³ at room temperature, depending on chemical composition. Viscosity spans a broad spectrum, from very low (water) to very high (glycerol or syrup). Boiling points and freezing points determine the conditions under which a liquid remains in the liquid state. Surface tension results from cohesive forces at the air–liquid interface, influencing droplet formation and wetting. Liquids may be pure substances or mixtures, and many liquids are miscible (form homogeneous solutions) or immiscible (form separate phases).

Classification can be based on composition or interaction. Liquids are often categorized as polar (for example water, ethanol) or nonpolar (such as hexane), which affects solubility and interfacial behavior. They can be pure substances or mixtures, including solutions, emulsions, and suspensions. Special classes, like liquid crystals, combine fluidity with some degree of molecular order.

Liquids play crucial roles in many applications: as solvents, cooling and heating media, lubricants, reactants in industrial processes, and in biological systems (for example water in cells and blood). Safety and environmental considerations include flammability, toxicity, reactivity, and potential ecological impact, especially for volatile or persistent liquids.