logging in or signing up Chemistry Homework Help assignmenthelpn Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 22 Category: Education License: All Rights Reserved Like it (0) Dislike it (0) Added: January 30, 2012 This Presentation is Public Favorites: 0 Presentation Description Students can get Online chemistry help, Chemistry assignment help and Chemistry homework help with the expert online chemistry tutors. Chemistry is one of the subjects in which we provide homework and assignment help. Whether your problem related to Organic, Inorganic, Physical or Quantum Chemistry, we have 24 / 7 live online tutors available. assignmenthelp.net/chemistry_assignment_help.php Comments Posting comment... Premium member Presentation Transcript Chemistry Homework Help: Chemistry Homework Help An Overview Assignmenthelp.net Chemical Euilibrium: Chemical Euilibrium When the number of molecules leaving the liquid to vapour equals the number of molecules returning to the liquid from vapour equilibrium is said to be attained and is dynamic in nature. Equilibrium can be established for both physical and chemical processes and at this stage rate of forward and reverse reactions are equal.PowerPoint Presentation: Equilibrium constant, Kc is expressed as the concentration of products divided by reactants, each term raised to the stoichiometric coefficient. For reaction, a A + b B ƒ c C +d D Kc =( [C]^c [D]^d)/ ([A]^a [B]^b)PowerPoint Presentation: Equilibrium constant has constant value at a fixed temperature and at this stage all the macroscopic properties such as concentration, pressure, etc. become constant. For a gaseous reaction equilibrium constant is expressed as Kp and is written by replacing concentration terms by partial pressures in Kc expression. The direction of reaction can be predicted by reaction quotient Qc which is equal to Kc at equilibrium.PowerPoint Presentation: Le Chatelier’s principle states that the change in any factor such as temperature , pressure,concentration , etc. will cause the equilibrium to shift in such a direction so as to reduce or counteract the effect of the change. It can be used to study the effect of various factors such as temperature, concentration, pressure, catalyst and inert gases on the direction of equilibrium and to control the yield of products by controlling these factors.PowerPoint Presentation: Catalyst does not effect the equilibrium composition of a reaction mixture but increases the rate of chemical reaction by making available a new lower energy pathway for conversion of reactants to products and vice-versa.PowerPoint Presentation: All substances that conduct electricity in aqueous solutions are called electrolytes. Acids, bases and salts are electrolytes and the conduction of electricity by their aqueous solutions is due to anions and cations produced by the dissociation or ionization of electrolytes in aqueous solution. The strong electrolytes are completely dissociated. In weak electrolytes there is equilibrium between the ions and the unionized electrolyte molecules.PowerPoint Presentation: According to Arrhenius, acids give hydrogen ions while bases produce hydroxyl ions in their aqueous solutions. Brönsted -Lowry on the other hand, defined an acid as a proton donor and a base as a proton acceptor. When a Brönsted -Lowry acid reacts with a base, it produces its conjugate base and a conjugate acid corresponding to the base with which it reacts. Thus a conjugate pair of acid-base differs only by one proton.PowerPoint Presentation: Lewis further generalizsed the definition of an acid as an electron pair acceptor and a base as an electron pair donor. The expressions for ionization (equilibrium) constants of weak acids (Ka )and weak bases (Kb) are developed using Arrhenius definition. The degree of ionization and its dependence on concentration and common ion are discussed.PowerPoint Presentation: The pH scale (pH = -log[H+]) for the hydrogen ion concentration (activity) has been introduced and extended to other quantities ( pOH = – log[OH–]) ; pKa = –log[Ka] ; pKb = –log[Kb]; and pKw = –log[ Kw ] etc). The ionization of water has been considered and we note that the equation: pH + pOH = pKw is always satisfied. The salts of strong acid and weak base, weak acid and strong base, and weak acid and weak base undergo hydrolysis in aqueous solution.PowerPoint Presentation: The solutions which resist change in pH on dilution or with the addition of small amounts of acid or alkali are called Buffer Solutions. By Le Chatelier’s principle,if we increase the concentration of any one of the ions, it should combine with the ion of its opposite charge and some of the salt will be precipitated till once again Ksp = Qsp . Similarly,if the concentration of one of the ions is decreased, more salt will dissolve to increase the concentration of both the ions till once again Ksp = Qsp.this is the common ion effectFor further info: For further info http://www.assignmenthelp.net +1-617-874-1011 (USA) +44-117-230-1145 (UK) +61-7-5641-0117 (AUS) support@assignmenthelp.net http://www.assignmenthelp.net/rss.xml http://assignmenthelp.net/Assignment_Help_Podcasts/Poderator.xml You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.
Chemistry Homework Help assignmenthelpn Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 22 Category: Education License: All Rights Reserved Like it (0) Dislike it (0) Added: January 30, 2012 This Presentation is Public Favorites: 0 Presentation Description Students can get Online chemistry help, Chemistry assignment help and Chemistry homework help with the expert online chemistry tutors. Chemistry is one of the subjects in which we provide homework and assignment help. Whether your problem related to Organic, Inorganic, Physical or Quantum Chemistry, we have 24 / 7 live online tutors available. assignmenthelp.net/chemistry_assignment_help.php Comments Posting comment... Premium member Presentation Transcript Chemistry Homework Help: Chemistry Homework Help An Overview Assignmenthelp.net Chemical Euilibrium: Chemical Euilibrium When the number of molecules leaving the liquid to vapour equals the number of molecules returning to the liquid from vapour equilibrium is said to be attained and is dynamic in nature. Equilibrium can be established for both physical and chemical processes and at this stage rate of forward and reverse reactions are equal.PowerPoint Presentation: Equilibrium constant, Kc is expressed as the concentration of products divided by reactants, each term raised to the stoichiometric coefficient. For reaction, a A + b B ƒ c C +d D Kc =( [C]^c [D]^d)/ ([A]^a [B]^b)PowerPoint Presentation: Equilibrium constant has constant value at a fixed temperature and at this stage all the macroscopic properties such as concentration, pressure, etc. become constant. For a gaseous reaction equilibrium constant is expressed as Kp and is written by replacing concentration terms by partial pressures in Kc expression. The direction of reaction can be predicted by reaction quotient Qc which is equal to Kc at equilibrium.PowerPoint Presentation: Le Chatelier’s principle states that the change in any factor such as temperature , pressure,concentration , etc. will cause the equilibrium to shift in such a direction so as to reduce or counteract the effect of the change. It can be used to study the effect of various factors such as temperature, concentration, pressure, catalyst and inert gases on the direction of equilibrium and to control the yield of products by controlling these factors.PowerPoint Presentation: Catalyst does not effect the equilibrium composition of a reaction mixture but increases the rate of chemical reaction by making available a new lower energy pathway for conversion of reactants to products and vice-versa.PowerPoint Presentation: All substances that conduct electricity in aqueous solutions are called electrolytes. Acids, bases and salts are electrolytes and the conduction of electricity by their aqueous solutions is due to anions and cations produced by the dissociation or ionization of electrolytes in aqueous solution. The strong electrolytes are completely dissociated. In weak electrolytes there is equilibrium between the ions and the unionized electrolyte molecules.PowerPoint Presentation: According to Arrhenius, acids give hydrogen ions while bases produce hydroxyl ions in their aqueous solutions. Brönsted -Lowry on the other hand, defined an acid as a proton donor and a base as a proton acceptor. When a Brönsted -Lowry acid reacts with a base, it produces its conjugate base and a conjugate acid corresponding to the base with which it reacts. Thus a conjugate pair of acid-base differs only by one proton.PowerPoint Presentation: Lewis further generalizsed the definition of an acid as an electron pair acceptor and a base as an electron pair donor. The expressions for ionization (equilibrium) constants of weak acids (Ka )and weak bases (Kb) are developed using Arrhenius definition. The degree of ionization and its dependence on concentration and common ion are discussed.PowerPoint Presentation: The pH scale (pH = -log[H+]) for the hydrogen ion concentration (activity) has been introduced and extended to other quantities ( pOH = – log[OH–]) ; pKa = –log[Ka] ; pKb = –log[Kb]; and pKw = –log[ Kw ] etc). The ionization of water has been considered and we note that the equation: pH + pOH = pKw is always satisfied. The salts of strong acid and weak base, weak acid and strong base, and weak acid and weak base undergo hydrolysis in aqueous solution.PowerPoint Presentation: The solutions which resist change in pH on dilution or with the addition of small amounts of acid or alkali are called Buffer Solutions. By Le Chatelier’s principle,if we increase the concentration of any one of the ions, it should combine with the ion of its opposite charge and some of the salt will be precipitated till once again Ksp = Qsp . Similarly,if the concentration of one of the ions is decreased, more salt will dissolve to increase the concentration of both the ions till once again Ksp = Qsp.this is the common ion effectFor further info: For further info http://www.assignmenthelp.net +1-617-874-1011 (USA) +44-117-230-1145 (UK) +61-7-5641-0117 (AUS) support@assignmenthelp.net http://www.assignmenthelp.net/rss.xml http://assignmenthelp.net/Assignment_Help_Podcasts/Poderator.xml