Skip to main content

Kinetics of Oxidation of Substituted Phenols by Potassium Bromate | Chapter 02 | Theory and Applications of Chemistry Vol. 3

Kinetic methods of analysis are now accepted as standard analytical procedures for several of reactions, especially oxidation types. Though the reaction of phenols and substituted phenols by potassium bromate is well understood as an oxidative type, there was a need to understand and more evidence required against the participation of Br2 in the increasing rate of reaction with increasing acetic acid composition in the bromate oxidation of phenols. Present work explains the strange behaviour on the basis of formation of HBrO3 that is favoured in acidic medium.

Kinetics of oxidation of 3, 4-Dimethyl phenol, 4-sec-butyl phenol and 4-tert-butyl phenol in aqueous acetic acid - water medium in the temperature range of 308K to 321K were investigated. The reaction obeys first order kinetics with respect to [oxidant], [substrate] and [H+]. The active oxidising species was found to be HBrO3. A suitable mechanism in conformity with the kinetic observation has been proposed. Various activation parameters such as energy of activation (58.59, 61, 43, 65.38 KJ/mol), enthalpy change [56.03, 58.87, 62.82 KJ/mol], free energy change (73.19, 77.17, 77.82 KJ/mol) and entropy of activation (-55.7, -59.45 and -48.78 J/mol/deg) for 3: 4-dimethyl phenol, 4-sec-butyl phenol, 4-tert-butyl phenol at 308K, were obtained. A rate law has been derived on the basis of the data. The order of reactivity among the methyl substituted phenols is 3, 4-dimethyl phenol > p-cresol > phenol. The order of reactivity among higher alkyl substituted phenols is 4-tert-butyl phenol 4-sec-butyl phenol > 4-ethyl phenol >phenol.

Author(s) Details

Dr. Asha Mathew
Department of Chemistry, S.I.W.S. College, Wadala, Mumbai 400031, India.

View Volume: http://bp.bookpi.org/index.php/bpi/catalog/book/104
Labels:

Comments

Post a Comment

Popular posts from this blog

A Prospective Study about Safety and Efficacy of Perioperative Lidocaine Infusion | Chapter 09 | New Horizons in Medicine and Medical Research Vol. 8

 Opioids cause clinically significant side effects such as respiratory depression, immunosuppression, muscle rigidity, negative inotropism, nausea, vomiting, hyperalgesia, urine retention, postoperative ileus, and drowsiness. Perioperative opioids are a major contributor to the United States' and other countries' opioid epidemics. Non-opioid analgesics, particularly lidocaine, are becoming more common for perioperative use as a result of this. A total of 185 adult patients were randomly assigned to one of two groups: control group I (105 patients) [fentanyl group] or group ii (80 patients) [opioid-free anaesthesia group]. Lidocaine 1.5 mg/kg bolus followed by 1.5 mg/kg/h infusion intraoperatively, and 1.5-2 mg/kg/h infusion for 2-8 hours postoperatively were given to patients in both groups at anaesthetic induction. Intraoperatively, both groups received analgesic adjuvants such as diclofenac 75 mg, paracetamol 1 gm, and mgso4 30-50 mg/kg. If the mean arterial pressure (map)
Post a Comment
Read more

A Brief Study of Middleware Technologies: Programming Applications and Management Systems | Chapter 15 | Novel Research Aspects in Mathematical and Computer Science Vol. 1

  Many platforms, services, applications, hardware, and operating systems are connected through the middleware layer. Because the middleware layer abstracts much low-level complexity and makes applications and software systems portable, it allows disparate systems to interface and function together in harmony. Middleware technologies enable software engineers to swiftly construct software systems and applications, allowing developers to focus on more important tasks. This chapter examines several types of middleware systems and discusses middleware capabilities, middleware operation, middleware's function in cloud-based systems, and the best middleware platforms to use. Middleware systems are widely utilised and can be found in practically any software system or application. Middleware programmes provide as a link between many sorts of systems and protocols. They serve as a mechanism for various systems. To successfully exchange information, it runs on a variety of operating system
Post a Comment
Read more

Patients’ Perspective of Acute Post-operative Pain Management: A Multicentre Survey of Tertiary Hospitals in Maharashtra, India | Chapter 08 | New Horizons in Medicine and Medical Research Vol. 8

 When postoperative pain is adequately controlled, patients' satisfaction and patient-related outcomes (PROs) increase. Understanding the patients' perspective is crucial since it supports in the formulation of improvement strategies. Because wrong attitudes and assumptions might block pain alleviation, patients' attitudes and beliefs are critical. As a result, a multicenter study of patients' attitudes, beliefs, experiences, and satisfaction levels with acute postoperative pain management was done in Maharashtra's tertiary hospitals. In addition, the responses were examined to evaluate if the Acute Pain Service (APS) resulted in improved patient outcomes and satisfaction. A 13-item questionnaire adapted from previous studies was used to capture patients' experiences with postoperative pain treatment. The responses of 179 patients are included in the study. The findings revealed that 91.6 percent of patients experienced postoperative pain, with 75.5 percent
Post a Comment
Read more