Molecular Structure of 1-Benzofuran-5-carboxylic acid (CAS NO.90721-27-0):

Empirical Formula: C₉H₆O₃
Molecular Weight: 162.1421
H bond acceptors: 3
H bond donors: 1
Freely Rotating Bonds: 1
Polar Surface Area: 39.44 Å²
Index of Refraction: 1.649
Molar Refractivity: 43.32 cm³
Molar Volume: 118.8 cm³
Surface Tension: 57.4 dyne/cm
Density: 1.363 g/cm³
Flash Point: 150.7 °C
Enthalpy of Vaporization: 59.93 kJ/mol
Boiling Point: 325.6 °C at 760 mmHg
Vapour Pressure: 9.31E-05 mmHg at 25°C
Melting point: 189-190°C
Product Categories: Furan&Benzofuran

Hazard Codes: Xi
Risk Statements: 36/37/38
R36/37/38:Irritating to eyes, respiratory system and skin.
Safety Statements: 26-37/39
S26: In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. 
S37/39:Wear suitable gloves and eye/face protection.

  1-Benzofuran-5-carboxylic acid , with CAS number of 90721-27-0, can be called 1-Benzofuran-5-carboxylic acid ; 5-benzofurancarboxylic acid ; 90721-27-0 [RN] ; Benzofuran-5-carboxylic acid ; Benzofurane-5-carboxylic acid . It is a white to light yellow crystal powde.