The ability of a detergent solution to lower the surface tension of water is directly related to its concentration. Detergents are surfactants, which are compounds that have both hydrophilic water-loving and hydrophobic water-repelling parts. When added to water, the hydrophobic part of the detergent molecules tends to avoid water, while the hydrophilic part interacts with water molecules.As the concentration of the detergent solution increases, more detergent molecules are present in the solution. This leads to a higher number of detergent molecules at the air-water interface, which disrupts the hydrogen bonding between water molecules. As a result, the surface tension of the water decreases.However, this relationship between detergent concentration and surface tension reduction is not linear. At low concentrations, the surface tension decreases rapidly with increasing detergent concentration. But as the concentration increases further, the reduction in surface tension becomes less significant. Eventually, a point called the critical micelle concentration CMC is reached, where detergent molecules start to form micelles aggregates of surfactant molecules in the solution. Beyond the CMC, the surface tension remains relatively constant, even if the detergent concentration continues to increase.In summary, the concentration of a detergent solution has a significant effect on its ability to lower the surface tension of water. The surface tension decreases with increasing detergent concentration, but the effect becomes less significant as the concentration increases, eventually reaching a plateau at the critical micelle concentration.