CyclopentaneCyclopentane is a highly flammable alicyclic hydrocarbon with chemical formula C5H10 and CAS number 287-92-3, consisting of a ring of give carbon atoms each bonded with two hydrogen atoms above and below the plane. It occurs as a colorless liquid with a petrol-like odor.Cyclopentane is used in the synthetic resins and rubber adhesives and also as a blowing agent in the manufacture of polyurethane insulating foam, as found in many domestic appliances such as refrigerators and freezers, replacing environmentally damaging alternatives such as CFC-11 and HCFC-141b.NamesIUPAC nameCyclopentaneOther namespentamethyleneIdentifiersCAS Number287-92-3 ChEBICHEBI:23492 ChemSpider8896 EC Number206-016-6Jmol 3D modelInteractive imagePubChem9253RTECS numberGY2390000PropertiesChemical formulaC5H10Molar mass70.1 g/molAppearanceclear, colorless liquidOdormild, sweetDensity0.751 g/cm3Melting point−93.9 °C (−137.0 °F; 179.2 K)Boiling point49.2 °C (120.6 °F; 322.3 K)Solubility in water156 mg·l−1 (25 °C)[1]Solubilitysoluble in ethanol, acetone, etherVapor pressure400 mmHg (31 °C)[2]Acidity (pKa)~45Refractive index (nD)1.4065