Freezing point of Pure 2-methyl-2propanol is 25.5 degree Celsius, however it absorbs H2O when it on exposed to humid air. determine how many milligrams of H2O are present in sample If the freezing point of 100.0 grams of sample of 2-methyl-2-propanol =24.59C, (2methyl-2propanol has Kf=4.68Ckg/mol