... (mpa), 25 º C 0.7Relative density( water=1) 1.12Relative vapor density ( air=1) 2.79Appearance: Colorless, no cloudyOdor OdorlessPurity ≥ % 99 ... mg/kg ≤ 100Non-congealing gas-phase, % (v/v), ≤ 1.5 Grade Excellent First Appearance Colorless, no cloudy Colorless, no ... 99.5 Water, mg/kg≤ 10 20 Acidity, mg/kg≤ 1 1 Residue on evaporation, mg/kg≤ 100 100 Global warming potential ...