Place the tube in a water bath (about 50 C°,40 C°, 30 C° and 20 C°, respectively). Continue stirring for about 5 minutes while some slid KCl will be separated from the solution to the bottom of the tube when the solution was cooled down. Read and record the constant temperature of the saturated solution in the tube (constant about 3 minutes) in C° and convert to Kelvin (K).