To calculate the density of the potassium chloride solution, we can use the formula:Density = mass/volumeGiven the mass of the solution is 31.5 grams and the volume is 25.0 mL, we can plug these values into the formula:Density = 31.5 g / 25.0 mLDensity = 1.26 g/mLSo, the density of the potassium chloride solution at 25C is 1.26 g/mL.