How is turbidity measured in water samples?

Turbidity in water samples is primarily measured by assessing the intensity of light reflected or transmitted through a water sample. This measurement is based on the premise that suspended particles in the water scatter light. When a beam of light passes through the sample, particles present in the water will reflect and scatter that light, thereby reducing the amount of light that reaches a detector.

The more particles that are present in the water, the higher the turbidity level will be, which results in more scattering and less light being transmitted through the sample. Instruments used for measuring turbidity, such as turbidimeters, quantify this scattering effect and provide a numerical value that reflects the clarity or cloudiness of the water.

Other options may refer to different aspects of water quality but are not relevant to turbidity measurement. The temperature of water can affect the solubility of substances but does not measure turbidity directly. The chemical composition of the water can influence turbidity indirectly through the presence of certain compounds but does not quantify the turbidity itself. While particle size can influence turbidity, it is not a direct measurement technique; turbidity is assessed through light scattering initiated by the particles, regardless of their size.