Melting point :152-154 °C (lit.)
alpha :D +66° (in chloroform)
Boiling point :332.25°C (rough estimate)
Density :1.1450 (rough estimate)
refractive index :67.5 ° (C=1, CHCl3)
Flash point :9℃
storage temp. :2-8°C
solubility :Practically insoluble in water, soluble in ethanol (96 per cent) and in methanol.
form :powder
pka :pKa 4.28± 0.02(H2O,t =25,I=0.01) (Uncertain)
color :White to Almost white
optical activity :[α]25/D +66°, c = 1 in chloroform
Water Solubility :Insoluble in water.
Merck :14,6417
BRN :3591067
BCS Class :2
LogP :3.18
CAS DataBase Reference :22204-53-1(CAS DataBase Reference)
NIST Chemistry Reference :Naproxen(22204-53-1)
EPA Substance Registry System :2-Naphthaleneacetic acid, 6-methoxy-.alpha.-methyl-, (.alpha.S)- (22204-53-1)

Symbol(GHS):
Signal word:	Warning
Hazard statements:	Code Hazard statements Hazard class Category Signal word Pictogram P-Codes H302 Harmful if swallowed Acute toxicity,oral Category 4 Warning P264, P270, P301+P312, P330, P501 H315 Causes skin irritation Skin corrosion/irritation Category 2 Warning P264, P280, P302+P352, P321,P332+P313, P362 H319 Causes serious eye irritation Serious eye damage/eye irritation Category 2A Warning P264, P280, P305+P351+P338,P337+P313P H335 May cause respiratory irritation Specific target organ toxicity, single exposure;Respiratory tract irritation Category 3 Warning H411 Toxic to aquatic life with long lasting effects Hazardous to the aquatic environment, long-term hazard Category 2
Precautionary statements:	P202 Do not handle until all safety precautions have been read and understood. P273 Avoid release to the environment. P301+P312 IF SWALLOWED: call a POISON CENTER or doctor/physician IF you feel unwell. P302+P352 IF ON SKIN: wash with plenty of soap and water. P305+P351+P338 IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing. P308+P313 IF exposed or concerned: Get medical advice/attention.