The critical micelle concentration CMC of a surfactant like sodium dodecyl sulfate SDS is the concentration at which micelles begin to form in a solution. The CMC is dependent on factors such as temperature, ionic strength, and the presence of other solutes.For sodium dodecyl sulfate SDS in an aqueous solution at 25C, the CMC is typically reported to be around 8-10 mM millimolar . However, it is important to note that the CMC can vary depending on the specific conditions of the solution, such as the presence of salts or other additives. To determine the exact CMC for a specific solution, experimental methods such as surface tension measurements, conductivity measurements, or fluorescence techniques can be used.