This document discusses several topics related to chemical equilibria in solutions, including:
- The law of mass action and how it applies to ionic equilibria in solutions.
- Factors that affect the degree of dissociation of electrolytes in solutions, such as the nature of the solute and solvent, concentration, and temperature.
- Concepts like solubility products, acid-base equilibria in water including the autoionization of water and pH, and Ostwald's dilution law for weak electrolytes.
- Limitations of Ostwald's law for strong electrolytes and how the pH scale provides an easier way to compare hydrogen ion concentrations in solutions.
This document provides an overview of acid-base titration including definitions, concepts, and procedures. It discusses the Arrhenius, Bronsted-Lowry, and Lewis definitions of acids and bases. It explains the process of ionization and factors that influence it such as relative permittivity. Key aspects of acid-base titration covered include types of reactions that can occur, use of indicators, and standards. The document also discusses acid and base ionization constants and how they relate to strength. Examples are provided to illustrate acid strength calculations and indicator color changes corresponding to pH.
This document discusses chemical equilibrium. It begins by defining chemical equilibrium as the state where the rates of the forward and reverse reactions are equal, and the amounts of reactants and products remain constant. It then provides examples of chemical equilibrium calculations for reactions involving gases, solubility of ionic compounds, and acid-base reactions. Key aspects that determine the position of equilibrium, such as concentration, temperature, and the equilibrium constant K, are also explained.
University of Southern Mindanao
2 BS Pharmacy A (AY: 2023-2024)
PHARM 12 - Physical Pharmacy
All About pH and Buffers This contains the topics about Acids, Bases and Buffers.
REFERENCES
7.1A: Acid-Base Theories and Concepts. (2017, June 3). Chemistry LibreTexts. https://chem.libretexts.org/Bookshelves/Inorganic_Chemistry/Map%3A_Inorganic_Chemistry_(Housecroft)/07%3A_Acids_bases_and_ions_in_aqueous_solution/7.01%3A_Introduction/7.1A%3A_Acid-Base_Theories_and_Concepts#:~:text=There%20are%20three%20primary%20theories
Applied Physical Pharmacy (2014) McGraw-Hill Education. ISBN: 978-0-07-180442-4
Abdella, S., Abid, F., Youssef, S. H., Kim, S., Afinjuomo, F., Malinga, C., Song, Y., & Garg, S. (2023). pH and its applications in targeted drug delivery. Drug Discovery Today, 28(1), 103414. https://doi.org/10.1016/j.drudis.2022.103414
Admin. (2022, December 1). Ionization Of Water - Nature of Water, Detailed explanation of Self Ionization of Water and Pure water’s Ion. BYJUS. https://byjus.com/chemistry/ionization-of-water/
Byju’s. (2022, July 4). Is NaCl it An Acid or Base-. https://byjus.com/question-answer/is-nacl-an-acid-or-base/
Johnston, M. (2023, April 9). Hydrogen: What’s the difference between H, H2, H+, H- and OH- ? Watermatters.
https://www.watermatters.ca/blogs/articles/hydrogen-what-s-the-difference-between-h-h2-h-h-and-oh
Libretexts. (2023, July 18). 14.2: Ionization of Water. Chemistry LibreTexts. https://chem.libretexts.org/Bookshelves/General_Chemistry/ChemPRIME_(Moore_et_al.)/14%3A_Ionic_Equilibria_in_Aqueous_Solutions/14.02%3A_Ionization_of_Water
Niederquell, A., Stoyanov, E. V., & Kuentz, M. (2023). Physiological buffer effects in drug supersaturation - A mechanistic study of hydroxypropyl cellulose as precipitation inhibitor. Journal of Pharmaceutical Sciences, 112(7), 1897–1907. https://doi.org/10.1016/j.xphs.2023.02.013
pH of Salts in Water | Department of Chemistry | University of Washington. (n.d.). https://chem.washington.edu/lecture-demos/ph-salts-water#:~:text=Since%20this%20reaction%20produces%20OH,sodium%20acetate%20solution%20is%20basic.
The document discusses pH, electrical conductivity, and oxidation-reduction potential in soils.
pH measures the concentration of hydrogen ions in soil and indicates whether the soil is acidic or alkaline on a scale of 0-14. Electrical conductivity measures the total soluble salts in soil and indicates soil fertility. Oxidation-reduction potential measures the capacity of soil to accept or donate electrons and indicates whether the soil environment is oxidized or reduced. Together, these measurements provide important information about the chemical characteristics of soils.
This document provides an overview of acid-base titration and volumetric analysis. It defines key terms like titration, indicator, equivalence point, and standardization. It describes different types of titrations including direct, indirect, and back titration. Acid-base concepts are explained based on Arrhenius, Bronsted-Lowry, and Lewis theories. The document also discusses the ionic product of water, common ion effect, classification of indicators, and theories of indicators including Ostwald and chromophore theories.
This document provides an overview of acid-base titration including definitions, concepts, and procedures. It discusses the Arrhenius, Bronsted-Lowry, and Lewis definitions of acids and bases. It explains the process of ionization and factors that influence it such as relative permittivity. Key aspects of acid-base titration covered include types of reactions that can occur, use of indicators, and standards. The document also discusses acid and base ionization constants and how they relate to strength. Examples are provided to illustrate acid strength calculations and indicator color changes corresponding to pH.
This document discusses chemical equilibrium. It begins by defining chemical equilibrium as the state where the rates of the forward and reverse reactions are equal, and the amounts of reactants and products remain constant. It then provides examples of chemical equilibrium calculations for reactions involving gases, solubility of ionic compounds, and acid-base reactions. Key aspects that determine the position of equilibrium, such as concentration, temperature, and the equilibrium constant K, are also explained.
University of Southern Mindanao
2 BS Pharmacy A (AY: 2023-2024)
PHARM 12 - Physical Pharmacy
All About pH and Buffers This contains the topics about Acids, Bases and Buffers.
REFERENCES
7.1A: Acid-Base Theories and Concepts. (2017, June 3). Chemistry LibreTexts. https://chem.libretexts.org/Bookshelves/Inorganic_Chemistry/Map%3A_Inorganic_Chemistry_(Housecroft)/07%3A_Acids_bases_and_ions_in_aqueous_solution/7.01%3A_Introduction/7.1A%3A_Acid-Base_Theories_and_Concepts#:~:text=There%20are%20three%20primary%20theories
Applied Physical Pharmacy (2014) McGraw-Hill Education. ISBN: 978-0-07-180442-4
Abdella, S., Abid, F., Youssef, S. H., Kim, S., Afinjuomo, F., Malinga, C., Song, Y., & Garg, S. (2023). pH and its applications in targeted drug delivery. Drug Discovery Today, 28(1), 103414. https://doi.org/10.1016/j.drudis.2022.103414
Admin. (2022, December 1). Ionization Of Water - Nature of Water, Detailed explanation of Self Ionization of Water and Pure water’s Ion. BYJUS. https://byjus.com/chemistry/ionization-of-water/
Byju’s. (2022, July 4). Is NaCl it An Acid or Base-. https://byjus.com/question-answer/is-nacl-an-acid-or-base/
Johnston, M. (2023, April 9). Hydrogen: What’s the difference between H, H2, H+, H- and OH- ? Watermatters.
https://www.watermatters.ca/blogs/articles/hydrogen-what-s-the-difference-between-h-h2-h-h-and-oh
Libretexts. (2023, July 18). 14.2: Ionization of Water. Chemistry LibreTexts. https://chem.libretexts.org/Bookshelves/General_Chemistry/ChemPRIME_(Moore_et_al.)/14%3A_Ionic_Equilibria_in_Aqueous_Solutions/14.02%3A_Ionization_of_Water
Niederquell, A., Stoyanov, E. V., & Kuentz, M. (2023). Physiological buffer effects in drug supersaturation - A mechanistic study of hydroxypropyl cellulose as precipitation inhibitor. Journal of Pharmaceutical Sciences, 112(7), 1897–1907. https://doi.org/10.1016/j.xphs.2023.02.013
pH of Salts in Water | Department of Chemistry | University of Washington. (n.d.). https://chem.washington.edu/lecture-demos/ph-salts-water#:~:text=Since%20this%20reaction%20produces%20OH,sodium%20acetate%20solution%20is%20basic.
The document discusses pH, electrical conductivity, and oxidation-reduction potential in soils.
pH measures the concentration of hydrogen ions in soil and indicates whether the soil is acidic or alkaline on a scale of 0-14. Electrical conductivity measures the total soluble salts in soil and indicates soil fertility. Oxidation-reduction potential measures the capacity of soil to accept or donate electrons and indicates whether the soil environment is oxidized or reduced. Together, these measurements provide important information about the chemical characteristics of soils.
This document provides an overview of acid-base titration and volumetric analysis. It defines key terms like titration, indicator, equivalence point, and standardization. It describes different types of titrations including direct, indirect, and back titration. Acid-base concepts are explained based on Arrhenius, Bronsted-Lowry, and Lewis theories. The document also discusses the ionic product of water, common ion effect, classification of indicators, and theories of indicators including Ostwald and chromophore theories.
This document discusses ionic equilibrium and acid-base concepts. It defines strong and weak electrolytes, and explains that strong electrolytes completely ionize while weak electrolytes partially ionize. The degree of ionization and ionization constant are introduced to quantify the ionization of weak electrolytes. Factors that affect the degree of ionization are also discussed. Different theories of acids and bases are presented, including Arrhenius, Bronsted-Lowry, and Lewis concepts. The limitations of each theory and advantages of broader theories are described. Conjugated acid-base pairs are defined in relation to Bronsted acids and bases.
The document discusses pH and acid-base chemistry, including the definitions of acids and bases, acid-base reactions, pH and pKa scales, autoionization of water, acid and base strength, and methods for measuring pH. Common acid-base concepts like conjugate acid-base pairs, strong vs weak acids, and calculations involving hydronium and hydroxide ion concentrations are explained. The properties and types of solutions such as concentration, solubility, dilution, and factors that affect solubility are also covered.
This solution exhibits nonideal behavior. Acetone and chloroform are both volatile liquids that contribute to the total vapor pressure. To determine if it is ideal or nonideal, we would need the individual vapor pressures of acetone and chloroform at 35°C and their mole fractions in order to use the modified Raoult's law equation and compare the calculated total pressure to the measured 260 torr.
The document discusses water, pH, and buffers. It covers the structure and polarity of water molecules, solubility in water, acids and bases, and how buffers maintain pH stability. Buffers work by having both weak acids and their conjugate bases reach equilibrium according to their dissociation constants in order to neutralize added acids or bases. The most important physiological buffers are bicarbonate and phosphate buffers that help regulate blood and intracellular pH.
This document provides information on solutions of non-electrolytes. It defines key terms like solute, solvent, saturated solution, and supersaturated solution. It explains how a solution forms via a 3 step process of solute separation, solvent separation, and solute-solvent interaction. Various methods of expressing concentration are described, including mass percentage, parts per million/billion, mole fraction, molarity, molality, and normality. Raoult's law and its limitations are discussed. Real solutions that deviate positively or negatively from Raoult's law are explained. Henry's law relating gas solubility to partial pressure is also summarized.
This document summarizes key concepts about types of chemical reactions and solution stoichiometry. It discusses water as a solvent, solubility, strong and weak electrolytes, and precipitation, acid-base, and oxidation-reduction reactions in solution. Calculations involve determining moles and masses of reactants and products using molarity, volumes, and balanced equations. Common indicators like phenolphthalein are used in acid-base titrations.
Chapter 13 Lecture on Solutions & Colligative PropertiesMary Beth Smith
The document summarizes key concepts about solutions from chapters 11-13, including:
- Solutions are homogeneous mixtures of two or more substances where the solute is uniformly dispersed in the solvent.
- Solubility is affected by intermolecular forces - "like dissolves like" with polar substances dissolving in polar solvents.
- Temperature and pressure can impact solubility, with solubility generally increasing with temperature and gas solubility directly proportional to pressure.
- There are various ways to express concentration, including molarity, molality, mole fraction, ppm, and mass percentage.
This document discusses several physico-chemical properties of drug molecules that are important for drug formulation and delivery, including physical state, melting point, boiling point, polarity, and solubility. It also covers acid-base properties of drugs and how pH and pKa values are used to characterize these properties. Buffers are described as solutions that can maintain a relatively constant pH when acids or bases are added.
This document discusses ionic equilibrium and electrolytes. It defines electrolytes as substances that conduct electricity when dissolved in water by dissociating into ions. Electrolytes are divided into strong and weak based on their degree of ionization. Strong electrolytes almost completely ionize while weak electrolytes ionize only partially. The document discusses Arrhenius theory of electrolytic dissociation and factors that affect the degree of ionization like concentration, temperature, and presence of a common ion. It also defines concepts like isohydric solutions and dissociation constants.
Definition, Ostwald’s dilution law, dissociation theory, ionization of water, common-ion effect, ionization constants of acid and bases, ionization of polyprotic electrolytes, solubility products and its application in pharmacy.
Solubility is defined as the maximum amount of solute that can dissolve in a solvent at equilibrium. The solubility product is the maximum product of ion concentrations of an electrolyte that can be in equilibrium with the undissolved solid phase. When an ionic solid dissolves, it dissociates into separate cations and anions. At equilibrium, the rates of dissolution and precipitation are equal. The solubility product principle states that the product of ion concentrations in a saturated solution is constant at a given temperature. The solubility product (Ksp) can be used to calculate solubility from ion concentrations or vice versa. Precipitation will occur if the ionic product (Q) is greater than Ksp when
Water makes up 65-70% of the human body. It has unique properties like high melting and boiling points due to hydrogen bonding between water molecules. The bent shape of water molecules gives them a partial positive and negative charge, allowing them to form hydrogen bonds with other water molecules. These bonds contribute to water's high heat capacity and heat of vaporization. Water's pH measures the concentration of hydronium ions, with values below 7 indicating acidity and above 7 indicating alkalinity. pH is important in biological and chemical systems and can be measured using indicators, meters, and the Henderson-Hasselbalch equation.
This document discusses the properties and importance of water and non-aqueous solvents. It notes that while water is a common solvent, it has limitations for reactions involving strong acids/bases or reducing agents. Non-aqueous solvents allow these types of reactions and can change product outcomes. Important properties of solvents discussed include melting/boiling points, heat of fusion/vaporization, dielectric constant, dipole moment, and viscosity - all of which influence a solvent's ability to dissolve different types of compounds. Non-aqueous solvents like liquid ammonia and sulfur dioxide expand the scope of chemical reactions.
This document discusses the application of conductance measurements in chemistry. It describes five uses: 1) determining the degree of dissociation of weak electrolytes, 2) determining ionization constants of acids, 3) determining solubility products of sparingly soluble salts, 4) calculating the ionic product of water, and 5) conductometric titration. Conductometric titration involves measuring conductivity during a titration to determine the endpoint, which occurs when conductivity remains constant as the neutralization point is reached. Factors that affect conductivity include the size, temperature, charge, and number of ions in solution.
This document provides an overview of acid-base chemistry concepts including:
1) Definitions of acids, bases, conjugate acid-base pairs, and amphiprotic species.
2) Explanations of acid and base dissociation constants and their relationships.
3) Descriptions of common ion and buffer effects.
4) Derivations of the Henderson-Hasselbalch equation for calculating pH in buffer solutions.
This document provides an overview of the key concepts in acid-base equilibria, including:
1. Acid-base equilibria can be understood as a two-step process involving competing equilibria and limiting reagent reactions.
2. There are four regimes of acid-base equilibria depending on whether the acid or base is initially present, partially consumed, exactly consumed, or in excess.
3. pH and pOH are used to characterize solutions based on concentrations of H3O+ and OH- ions, which are related by the water autoionization constant Kw.
The document discusses various topics related to solutions and electrochemistry. It begins by defining solutions and different ways of expressing concentration such as molarity, molality and normality. It then discusses solutions of gases in gases based on Henry's law and solutions of liquids in liquids, including completely miscible and partially miscible liquids. Other topics covered include solubility, vapor pressure of solutions, distillation, and colligative properties of solutions such as boiling point elevation, freezing point depression, and vapor pressure lowering. Measurement techniques for various colligative properties are also summarized.
This document discusses the measurement of pH. It begins by defining pH as the negative logarithm of the hydrogen ion concentration. It then discusses how pH meters work by measuring the voltage difference between a pH-sensitive glass electrode and a reference electrode. The voltage reading is proportional to the hydrogen ion concentration in solution, allowing the pH to be determined. The document provides details on the components of pH meters, including diagrams, and explains how they function to precisely measure pH.
Chem 132 principles of chemistry lab ii montgomeryAtherstonez
This document provides an introduction to principles of chemistry lab II, covering acids and bases, pH, buffers, and hydrolysis. Key points include:
- Acids and bases are classified as strong or weak based on their degree of ionization in aqueous solutions.
- The pH scale quantifies the concentration of hydronium ions in solution and relates it inversely to acidity.
- Buffers help maintain pH within a narrow range by consuming added hydronium or hydroxide ions.
- Indicators change color over specific pH ranges and can be used to approximate solution pH.
- Hydrolysis reactions involve the breaking of salt bonds in water and the formation of conjugate acid-base pairs.
Introduction
History
Acid & Base
Ionization of water
Definitions of pH
(1) Mathematical Definition
(2) pH
(3) pOH
Buffer solution
(1) Types
(2) Buffer action
(3) Biological buffer systems
Henderson – Hasselbalch Equation
Measurement of pH
(1) pH Scale
(2) pH indicators
(3) pH meter
pH in human body and nature
Importance
Conclusion
Reference
Corrosion is the destruction or deterioration of metallic materials due to chemical and electrochemical reactions with their environment. There are two main types of corrosion - dry corrosion caused by direct chemical reactions with gases, and wet corrosion caused by electrochemical reactions when metals are in contact with an electrolyte. Various factors influence the corrosion rate, including the metal properties, environmental conditions, and nature of corrosion products. Common corrosion control methods include cathodic protection, using corrosion inhibitors, and applying protective coatings to the metal surface.
Nanomaterials
There are several types of nanomaterials including carbon-based nanomaterials like fullerenes and carbon nanotubes, metal-based nanomaterials, and composite nanomaterials. Nanomaterials have unique properties compared to their bulk counterparts due to increased surface area and quantum effects at the nanoscale. They are synthesized using top-down methods that break down bulk materials or bottom-up methods that build nanomaterials up from individual atoms and molecules. Nanomaterials find applications in electronics, cosmetics, energy storage, and other fields due to their tunable optical, mechanical, and electrical properties.
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This solution exhibits nonideal behavior. Acetone and chloroform are both volatile liquids that contribute to the total vapor pressure. To determine if it is ideal or nonideal, we would need the individual vapor pressures of acetone and chloroform at 35°C and their mole fractions in order to use the modified Raoult's law equation and compare the calculated total pressure to the measured 260 torr.
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This document provides information on solutions of non-electrolytes. It defines key terms like solute, solvent, saturated solution, and supersaturated solution. It explains how a solution forms via a 3 step process of solute separation, solvent separation, and solute-solvent interaction. Various methods of expressing concentration are described, including mass percentage, parts per million/billion, mole fraction, molarity, molality, and normality. Raoult's law and its limitations are discussed. Real solutions that deviate positively or negatively from Raoult's law are explained. Henry's law relating gas solubility to partial pressure is also summarized.
This document summarizes key concepts about types of chemical reactions and solution stoichiometry. It discusses water as a solvent, solubility, strong and weak electrolytes, and precipitation, acid-base, and oxidation-reduction reactions in solution. Calculations involve determining moles and masses of reactants and products using molarity, volumes, and balanced equations. Common indicators like phenolphthalein are used in acid-base titrations.
Chapter 13 Lecture on Solutions & Colligative PropertiesMary Beth Smith
The document summarizes key concepts about solutions from chapters 11-13, including:
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- There are various ways to express concentration, including molarity, molality, mole fraction, ppm, and mass percentage.
This document discusses several physico-chemical properties of drug molecules that are important for drug formulation and delivery, including physical state, melting point, boiling point, polarity, and solubility. It also covers acid-base properties of drugs and how pH and pKa values are used to characterize these properties. Buffers are described as solutions that can maintain a relatively constant pH when acids or bases are added.
This document discusses ionic equilibrium and electrolytes. It defines electrolytes as substances that conduct electricity when dissolved in water by dissociating into ions. Electrolytes are divided into strong and weak based on their degree of ionization. Strong electrolytes almost completely ionize while weak electrolytes ionize only partially. The document discusses Arrhenius theory of electrolytic dissociation and factors that affect the degree of ionization like concentration, temperature, and presence of a common ion. It also defines concepts like isohydric solutions and dissociation constants.
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Introduction
History
Acid & Base
Ionization of water
Definitions of pH
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(2) Buffer action
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(2) pH indicators
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Importance
Conclusion
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Syllabus
Chapter-1
Introduction to objective, scope and outcome the subject
Chapter 2
Introduction: Scope and Specialization of Civil Engineering, Role of civil Engineer in Society, Impact of infrastructural development on economy of country.
Chapter 3
Surveying: Object Principles & Types of Surveying; Site Plans, Plans & Maps; Scales & Unit of different Measurements.
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Levelling: Instrument used Object of levelling, Methods of levelling in brief, and Contour maps.
Chapter 4
Buildings: Selection of site for Buildings, Layout of Building Plan, Types of buildings, Plinth area, carpet area, floor space index, Introduction to building byelaws, concept of sun light & ventilation. Components of Buildings & their functions, Basic concept of R.C.C., Introduction to types of foundation
Chapter 5
Transportation: Introduction to Transportation Engineering; Traffic and Road Safety: Types and Characteristics of Various Modes of Transportation; Various Road Traffic Signs, Causes of Accidents and Road Safety Measures.
Chapter 6
Environmental Engineering: Environmental Pollution, Environmental Acts and Regulations, Functional Concepts of Ecology, Basics of Species, Biodiversity, Ecosystem, Hydrological Cycle; Chemical Cycles: Carbon, Nitrogen & Phosphorus; Energy Flow in Ecosystems.
Water Pollution: Water Quality standards, Introduction to Treatment & Disposal of Waste Water. Reuse and Saving of Water, Rain Water Harvesting. Solid Waste Management: Classification of Solid Waste, Collection, Transportation and Disposal of Solid. Recycling of Solid Waste: Energy Recovery, Sanitary Landfill, On-Site Sanitation. Air & Noise Pollution: Primary and Secondary air pollutants, Harmful effects of Air Pollution, Control of Air Pollution. . Noise Pollution Harmful Effects of noise pollution, control of noise pollution, Global warming & Climate Change, Ozone depletion, Greenhouse effect
Text Books:
1. Palancharmy, Basic Civil Engineering, McGraw Hill publishers.
2. Satheesh Gopi, Basic Civil Engineering, Pearson Publishers.
3. Ketki Rangwala Dalal, Essentials of Civil Engineering, Charotar Publishing House.
4. BCP, Surveying volume 1
This presentation was provided by Steph Pollock of The American Psychological Association’s Journals Program, and Damita Snow, of The American Society of Civil Engineers (ASCE), for the initial session of NISO's 2024 Training Series "DEIA in the Scholarly Landscape." Session One: 'Setting Expectations: a DEIA Primer,' was held June 6, 2024.
বাংলাদেশের অর্থনৈতিক সমীক্ষা ২০২৪ [Bangladesh Economic Review 2024 Bangla.pdf] কম্পিউটার , ট্যাব ও স্মার্ট ফোন ভার্সন সহ সম্পূর্ণ বাংলা ই-বুক বা pdf বই " সুচিপত্র ...বুকমার্ক মেনু 🔖 ও হাইপার লিংক মেনু 📝👆 যুক্ত ..
আমাদের সবার জন্য খুব খুব গুরুত্বপূর্ণ একটি বই ..বিসিএস, ব্যাংক, ইউনিভার্সিটি ভর্তি ও যে কোন প্রতিযোগিতা মূলক পরীক্ষার জন্য এর খুব ইম্পরট্যান্ট একটি বিষয় ...তাছাড়া বাংলাদেশের সাম্প্রতিক যে কোন ডাটা বা তথ্য এই বইতে পাবেন ...
তাই একজন নাগরিক হিসাবে এই তথ্য গুলো আপনার জানা প্রয়োজন ...।
বিসিএস ও ব্যাংক এর লিখিত পরীক্ষা ...+এছাড়া মাধ্যমিক ও উচ্চমাধ্যমিকের স্টুডেন্টদের জন্য অনেক কাজে আসবে ...
How to Fix the Import Error in the Odoo 17Celine George
An import error occurs when a program fails to import a module or library, disrupting its execution. In languages like Python, this issue arises when the specified module cannot be found or accessed, hindering the program's functionality. Resolving import errors is crucial for maintaining smooth software operation and uninterrupted development processes.
This document provides an overview of wound healing, its functions, stages, mechanisms, factors affecting it, and complications.
A wound is a break in the integrity of the skin or tissues, which may be associated with disruption of the structure and function.
Healing is the body’s response to injury in an attempt to restore normal structure and functions.
Healing can occur in two ways: Regeneration and Repair
There are 4 phases of wound healing: hemostasis, inflammation, proliferation, and remodeling. This document also describes the mechanism of wound healing. Factors that affect healing include infection, uncontrolled diabetes, poor nutrition, age, anemia, the presence of foreign bodies, etc.
Complications of wound healing like infection, hyperpigmentation of scar, contractures, and keloid formation.
How to Make a Field Mandatory in Odoo 17Celine George
In Odoo, making a field required can be done through both Python code and XML views. When you set the required attribute to True in Python code, it makes the field required across all views where it's used. Conversely, when you set the required attribute in XML views, it makes the field required only in the context of that particular view.
A workshop hosted by the South African Journal of Science aimed at postgraduate students and early career researchers with little or no experience in writing and publishing journal articles.
How to Build a Module in Odoo 17 Using the Scaffold MethodCeline George
Odoo provides an option for creating a module by using a single line command. By using this command the user can make a whole structure of a module. It is very easy for a beginner to make a module. There is no need to make each file manually. This slide will show how to create a module using the scaffold method.
Film vocab for eal 3 students: Australia the movie
Physical chemistry 3_Chemical equilibrium.pptx
1. An amazing fact
Feeding the earth’s enormous (and growing)
population
Simple chemical reaction involving
the reaction of nitrogen with hydrogen to form
ammonia
Chemistry
The Molecular Nature of Matter
Neil D. Jespersen
St. John’s University, New York
James E. Brady
St. John’s University, New York
In collaboration with Alison Hyslop
St. John’s University, New York
100 million tons of ammonia annually, with most of it going to agricultural uses as a
fertilizer
2. THEORETICAL PRINCIPLES OF REACTIONS
IN
SOLUTION EQUILIBRIA
Dr. B. Santosh Kumar
&
Dr.K.V.Nagalakshmi
PHYSICAL CHEMISTRY
3. TOPICS
Law of mass action
Factors effecting chemical reactions in solution
Electrolytic dissociation
Solubility product
Effects of acids and Temperature on precipitates
4. TOPICS
Acid-Base equilibria in water
Oswald dilution law
Strengths of acids and bases
Dissociation of poly proticacid
Titration curve of weak polyprotic acid
Common ion effect
Ionic product of water
Hydrogen ion exponent
Hydrolysis of salts
Degree of hydrolysis
Buffer solution
5. Chemical Equilibrium
Every reversible chemical reaction can reached the
state where the concentrations of products and
reactants remain constant over time and there are
no visible changes in the system.
That particular state is called equilibrium state and
there are no observable changes as times goes by.
Reactants Products
6. Characteristics of chemical equilibrium
• Dynamic in nature
• Constancy in some observable properties
like color, pressure, concentration, density
and temperature etc..
• Equilibrium state can be affected by
altering some factors like pressure,
volume, concentration and temperature.
7. Law of mass action
“The rate of any chemical reaction is
proportional to the product of the active
masses of the reacting substances, with each
mass raised to a power equal to the
coefficient that occurs in the chemical
equation”
aA + bB cC + dD
Cato M.Guldberg and Peter Waage
8. Chemical reactions in solution
Electrolyte (AB) is dissolved in water and
a small
fraction of it dissociates to form ions (A+
and B–).
When the equilibrium has been reached
between the undissociated and the free
ions
AB A+ + B-
The fraction of the amount of the electrolyte in
solution present as free ions is called the Degree
of dissociation.
9. The degree of dissociation (x) =
amount dissociated (mol/L)
initial concentration (mol/L)
On applying the Law of Mass Action
[A+][B+]
[AB]
K =
x =
10. Factors affecting the reactions in solutions
• Nature of Solute
• Nature of the solvent
• Concentration
• Temperature
Strong acids and strong bases, and the salts obtained
by their interaction are almost completely dissociated
in solution. On the other hand, weak acids and weak
bases and their salts are feebly dissociated.
This effect of the solvent is measured by its ‘dielectric
constant’. The dielectric constant of a solvent may be
defined as its capacity to weaken the force of
attraction between the electrical charges
The extent of dissociation of an electrolyte is inversely
proportional to the concentration of its solution.
The higher the temperature greater is the
dissociation. At high temperature the increased
molecular velocities overcome the forces of attraction
between the ions and consequently the dissociation is
great.
11. Solubility product
An ionic solid substance (AgCl) dissolves in water, it
dissociates to give separate cations (Ag+) and anions (Cl-)
As the concentration of the ions in solution increases, they
collide and reform the solid phase.
Dynamic equilibrium is established between the solid phase
and the cations and anions in solution
AgCl Ag+ + Cl-
12. A Saturated solution is a solution in which the dissolved
and undissolved solute are in equilibrium.
A saturated solution represents the limit of a solute’s
ability to dissolve in a given solvent.
This is a measure of the “solubility” of the solute.
The Solubility (S) of a substance in a solvent is the
concentration in the saturated solution.
Solubility of a solute may be represented in grams per
100 ml of solution. It can also be expressed in
moles per litre.
The value of solubility of a substance depends on the
solvent and the temperature.
13. Applying the Law of Mass Action
[Ag+][Cl-]
[AgCl]
K =
The amount of AgCl in contact with saturated
solution does not change with time and the
factor [AgCl] remains the same.
Thus the equilibrium expression becomes
Ksp = [Ag+] [Cl–]
The product [Ag+] [Cl–] in the Ksp expression above is
also called the Ionic Product or Ion Product.
14. The Ksp expression may be stated as the product
of the concentration of ions (mol/l) in the
saturated solution at a given temperature is
constant.
This is called the Solubility product principle.
15. ACID-BASE EQUILIBRIUM IN WATER
Autoionization of Water
Sensitive instruments, pure water is observed to
weakly conduct electricity, indicating the presence of
very small concentrations of ions.
They arise from the very slight self-ionization, or
autoionization
16. On applying Law of Mass Action
water is a pure liquid, with a constant 55.6 molar
concentration, it does not appear in this equilibrium law
Because of the importance of the autoionization
equilibrium,
its equilibrium constant is given the special symbol, Kw,
that is called the ion product constant of water.
According to equilibrium law
17. Omit the water molecule that carries the hydrogen ion
and write H+ in place of H3O+
The equilibrium equation for the autoionization of water
then simplifies to
In pure water, the concentrations of H+ and OH- produced by
the autoionization are equal.
The concentrations have the following values at 25 °C.
[H+] = [OH-] = 1.0 × 10-7 mol L-1
Kw = (1.0 × 10-7) × (1.0 × 10-7) = 1.0 × 10-14
Therefore, at 25 °C,
18. Criteria for Acidic, Basic, and Neutral Solutions
Neutral solution [H3O+] = [OH-]
Acidic solution [H3O+] > [OH-]
Basic solution [H3O+] < [OH-]
consequences of the autoionization of water
In any aqueous solution, there are always both H3O+
and OH- ions, regardless of what solutes are present.
This means in a solution of the acid HCl there is some
OH-, and in a solution of the base NaOH, there is
some H3O+.
We call a solution acidic or basic depending on which
ion has the largest concentration.
19. Ostwald’s Dilution Law
According to the Arrhenius theory of dissociation,
an electrolyte dissociates into ions in water solutions.
These ions are in a state of equilibrium with the
undissociated molecules.
This equilibrium is called the Ionic equilibrium.
Ostwald noted that the Law of Mass Action can be
applied to the ionic equilibrium as in the case of
chemical equilibria.
20. Let us consider a binary electrolyte AB which dissociates
in solution to form the ions A+ and B–.
Let C moles per litre be the concentration of the electrolyte and
α (alpha) its degree of dissociation.
The concentration terms at equilibrium may be written as
[AB] = C (1 – α) mol litre– 1
[A+] = C α mol litre– 1
[B–] = C α mol litre– 1
Applying the Law of Mass Action :
21. The equilibrium constant “Kc” is called the Dissociation constant
or Ionization constant. Constant at a constant temperature
If one mole of an electrolyte be dissolved in V litre of the solution,
22. V is known as the Dilution or the solution.
This expression which correlates the variation of the degree of dissociation
of an electrolyte with dilution, is known as Ostwald’s Dilution Law.
For Weak Electrolytes
For weak electrolytes, the value of α is very small as compared to 1,
so that in most of the calculation we can take (1 – α) = 1.
Thus the Ostwald’s Dilution Law expression becomes
It implies that the degree of dissociation of a weak electrolyte is proportional
to the square root of the dilution
23. For Strong Electrolytes
For strong electrolytes, the value of α is large and it cannot be neglected
in comparison with 1
which gives a quadratic equation
α2 + α KcV – KcV = 0
from this equation the value of α can be evaluated.
24. Limitation of Ostwald’s Law
Ostwald’s Dilution law holds good only for weak
electrolytes and fails completely when applied to
strong electrolytes.
For strong electrolytes, which are highly ionised in
solution, the value of the dissociation constant K, far
from remaining constant, rapidly falls with dilution.
25. Factors that explain the failure of Ostwald’s law in case
of strong electrolytes
(1) The law is based on Arrhenius theory which assumes that only
a fraction of the electrolyte is dissociated at ordinary dilutions
and complete dissociation occurs only at infinite dilution.
(2) The Ostwald’s law is derived on the assumption that the Law
of Mass Action holds for the ionic equilibria as well. But when
the concentration of ions is very high, the presence of charges
affects the equilibrium. Thus the Law of Mass Action in its
simple form cannot be applied.
(3) The ions obtained by dissociation may get hydrated and may
affect the concentration terms. Better results are obtained by
using activities instead of concentrations.
26. For weak acids and bases, the molar concentrations of
H+ and OH- are very small
Writing and comparing two exponential values is not
always easy
A Danish chemist, S. P. L. Sørenson suggested an easier
approach to make comparisons of small values of [H+]
easier, called the pH of the solution
pH = -log [H+]
[H+] = 10-pH
Hydrogen ion exponent
27. pH is that it is a measure of the acidity of a solution. Hence, we may
define acidic, basic, and neutral in terms of pH values.
At 25 °C, in pure water, or in any solution that is neutral,
[H+] = [OH-] = 1.0 × 10-7 M
Therefore, the pH of a neutral solution at 25 °C is 7.00.
Acidic solution [H+] is larger than 10-7 M and so has a pH less than
7.00.
Thus, as a solution’s acidity increases, its pH decreases.
A basic solution is one in which the value of [H+] is less than 10-7 M
and so has a pH
that is greater than 7.00. As a solution’s acidity decreases, its pH
increases. At 25 °C:
pH = 7.00 Neutral solution
pH < 7.00 Acidic solution
pH > 7.00 Basic solution
28. Add a concentrated solution of a soluble lead compound,
such as Pb(NO3)2
increased concentration of Pb2+ in the PbCl2 solution
will drive the position of equilibrium to the left, causing
some PbCl2 to precipitate.
Le Châtelier’s principle the net result being that PbCl2 is
less soluble in a solution that contains Pb2+ from another
source than it is in pure water.
If a concentrated solution of a soluble chloride salt such
as NaCl is added to the saturated PbCl2 solution. The
added Cl- will drive the equilibrium to the left, reducing
the amount of dissolved PbCl2.
Common ion effect
29. Addition of a few drops of concentrated HCl, forced the
equilibrium to shift to the left. This caused some white
crystals of solid NaCl to precipitate. (Michael Watson)
Common ion effect
30. “The reduction of the degree of dissociation of a
salt by the addition of a common-ion is called
the Common-ion effect”
The common ion effect can dramatically lower
the solubility of a salt, as Example 18.5
demonstrates.
Common ion effect
31. Hydrolysis of salts
The salt of a weak acid, HA and a strong base dissolves in
water to form the anion A–. The A– anion tends to react
with water by drawing a proton (H+) from its molecule to
form the unionised molecule.
The reaction of an anion or cation with water
accompanied by cleavage of O–H bond is called
Hydrolysis.
the salt of a weak base, BOH, and a strong acid dissolves in
water to form the cation B+. The cation B+ reacts with water
by accepting OH– ions from its molecule.
32. The term hydrolysis is derived from hydro, meaning
water, and lysis, meaning breaking.
It may be noted that in anionic hydrolysis In solution
becomes slightly basic (pH > 7) due to the generation
of excess OH– ions.
In cationic hydrolysis, there is excess of H+ ions which
makes the solution slightly acidic (pH < 7).
Classification of different salts yypes according to their hydrolytic
behaviour:
(1) Salts of Weak acids and Strong bases
(2) Salts of Weak bases and Strong acids
(3) Salts of Weak acids and Weak bases
33. Why NaCl solution is neutral ?
NaCl dissociates in water to give the anion Cl–. HCl and
Cl– constitute an acid-base conjugate pair.
Since HCl is a strong acid, Cl– is very weak base. Cl– is unable
to accept a proton (H+) from an acid, particularly water. That is
why Cl– does not hydrolyse. It cannot generate OH– ions as
follows:
34. Salts of Weak acids and Strong bases
Eg: Sodium acetate, CH3COONa, and sodium cyanide, NaCN
CH3COO- + H2O ⎯⎯→ CH3COOH + -OH
It ionises in aqueous solution to form the anion CH3COO–. Being
the conjugate base of a weak acid, CH3COOH, it is a relatively
strong base. Thus CH3COO– accepts H+ ion from water and
undergoes
hydrolysis.
CH3COONa. This is a salt of the weak acid, CH3COOH, and strong
base, NaOH.
The resulting solution is slightly basic due to excess OH– ions
present.
35. Salts of Weak bases and Strong acids
Eg: Ammonium chloride, ferric chloride, aluminium
chloride, and copper sulphate.
NH4+ is a Bronsted conjugate acid of the weak base
NH4OH. Therefore, it is a relatively strong acid.
It accepts OH– ion from water (H2O) and forms the
unionised NH4OH and H+ ion.
The accumulation of H+ ions in solution makes it
acidic.
36. Salts of Weak acids and weak bases
Eg: Ammonium acetate, ammonium cyanide and
ammonium fluoride
Both the anion and the cation produced by ionisation
of the salt undergo hydrolysis.
The resulting solution is neutral, basic or acidic
depending on the relative hydrolysis of the anions and
the cations.
37. Many chemical and biological systems are quite sensitive to
pH
pH of your blood should be, within the range of 7.35 to
7.42, either to 7.00 or to 8.00 causes death.
Lakes and streams with a pH less than 5 often cannot
support fish life.
Thus, a change in pH can produce unwanted effects, and
systems that are sensitive to pH must be protected from the
H+ or OH- that might be formed or consumed by some
reaction.
Buffer Solutions
“Buffer solution is one which maintains its pH
fairly constant even upon the addition of small
amounts of acid or base”
38. A buffer contains solutes that enable it to resist large changes in pH
when small amounts of either strong acid or strong base are added
to it.
Ordinarily, the buffer consists of two solutes, one a weak acid and
the other its conjugate base.
If the acid is molecular, then the conjugate base is supplied by a
soluble salt of the acid.
Types of buffer solutions:
(1) a weak acid together with a salt of the same acid with a strong
base. These are called Acid buffers
e.g., CH3COOH + CH3COONa.
(2) a weak base and its salt with a strong acid. These are called
Basic buffers. e.g., NH4OH + NH4Cl.
39. How a Buffer Works ??
Buffer must be able to neutralize either a strong acid or strong
base that is added. This is precisely what the conjugate acid and
base components of the buffer do.
Lets consider a buffer composed of acetic acid, CH3COOH, and
acetate ion, CH3COO-, supplied by a salt such as CH3COONa.
If we add extra H+ to the buffer (from a strong acid) the acetate
ion (the weak conjugate base) can react with it as follows.
H+(aq) + CH3COO-(aq) ----→ CH3COOH(aq)
The added H+ changes some of the buffer’s CH3COO-, to its
conjugate (weak) acid, CH3COOH.
This reaction prevents a large buildup of H+ and a corresponding
decrease in pH.
40. A similarly, the addition of strong base to the buffer. The OH-
from the strong base will react with some CH3COOH.
Thus, one member of a buffer team neutralizes H+ that might
get into the solution, and the other member neutralizes OH-.
CH3COOH(aq) + OH-(aq) ----→ CH3COO-(aq) + H2O
Understanding buffers is an important tool for chemists to
use in applications ranging from the protocols of a research
project to designing a consumer product.
Here the added OH- changes some of the buffer’s acid, CH3COOH, into
its conjugate base, CH3COO-. This prevents a buildup of OH-, which
would otherwise cause large increase in the pH.
41. Calculation of pH of buffer solution
The pH of an acid buffer can be calculated from the dissociation
constant, Ka, of the weak acid and the concentrations of the acid
and the salt used.
This relationship is called the Henderson-Hasselbalch equation or
simply Henderson equation.
42. Loss of the first proton to yield the HSO4- ion is complete, but
the loss of the second proton is incomplete and involves an
equilibrium.
Dissociation of polyprotic acids
Many acids capable of supplying more than one H+ per molecule.
Recall that these are called polyprotic acids.
Eg: sulfuric acid, H2SO4, carbonic acid, H2CO3, and phosphoric
acid, H3PO4.
These acids undergo ionization in a series of steps, each of
which releases one proton.
For weak polyprotic acids, such as H2CO3 and H3PO4, each
step is an equilibrium. Even sulfuric acid, which we consider a
strong acid, is not completely ionized.
43. Let’s consider the weak diprotic acid, H2CO3. In water, the acid
ionizes in two steps, each of which is an equilibrium that
transfers an H+ ion to a water molecule.
As usual, we can use H+ in place of H3O+ and simplify these
equations to give
Each step has its own ionization constant, Ka,
which we identify as Ka1 for the first step and
Ka2 for the second. For carbonic acid,
Each step has its own ionization constant, Ka, which we identify as
Ka1 for the first step and Ka2 for the second.
45. Triprotic Acids:
A triprotic acid (H3A) can undergo three dissociations and will
therefore have three dissociation constants: Ka1 > Ka2 > Ka3. Take,
for example the three dissociation steps of the common triprotic
acid phosphoric acid
46. Fractional Concentration of Conjugate Base Species
For example, a generic diprotic acid will generate three species
in solution: H2A, HA–, and A2-, and the fractional concentration
of HA–, which is given by: