3- Nitrophenol. physical properties

An important point emerges from a comparison of the physical properties of the isomeric nitrophenols (Table 24.2). We notice that o-nitrophenol has a much lower boiling point and much lower solubility in water than its isomers it is the only one of the three that is readily steam-distillable. How can these differences be accounted for ... 

Nitrophenyl esters were prepared in high yield (about 90%) by reaction of excess (10% or so) m-nitrophenol with the respective acid chlorides in the presence of a trace of pyridine at 145°C. The physical properties are listed in Table V. 

Laurence et al. [23, 24, 135] measured two solvatochromic scales for about 200 bases, each based on one reference hydrogen-bond donor, 4-nitrophenol or 4-nitroaniline, one standard state, the pure base, and one physical property, the enhanced bathochromic shift of the longest wavelength n n transition (with intramolecular charge-transfer character) upon hydrogen bonding. The solvatochromic comparison method was improved and inert solvents were carefully chosen [135] to fix the comparison lines of Equations 4.37 and 4.38 ... 

Physical and Chemical Properties. As can be seen from Table 3-2, the physical and chemical properties of 2-nitrophenol and 4-nitrophenol have been sufficiently characterized to permit estimation of its environmental fate. However, there are considerable variations in the reported values of some of the physical data, such as water solubility and vapor pressure, in the literature. Knowledge of more accurate vapor pressure and water solubility data are important in predicting the volatility of the nitrophenols from water and soil. 

Samuel Cohen, Professor and Vice Chair, Department of Pathology and Microbiology, University of Nebraska Medical Center, Ohama, Nebraska Dr. Loren Koller, Professor and Dean, College of Veterinary Medicine, Oregon State University, Corvallis, Oregon and Dr. Frederick Oehme, Director, Comparative Toxicology Laboratories, Kansas State University, Manhattan, Kansas. These experts collectively have knowledge of 2- and 4-nitrophenol s physical and chemical properties, toxicokinetics, key health end points, mechanisms of action, human and animal exposure, and quantification of risk to humans. All reviewers were selected in conformity with the conditions for peer review specified in the Comprehensive Environmental Response, Compensation, and Liability Act of 1986, Section 104. 

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