1) The equivalence point occurs when the moles of acid and base are equal, while the endpoint is the point at which a physical indicator change occurs, which should be very close to the equivalence point.
2) Titration curves for strong acids/bases show a pH of 7 at the equivalence point, while weak acids/bases curves depend on the acid/base dissociation constants and the Henderson-Hasselbalch equation.
3) Polyprotic acids and polybasic bases have multiple equivalence points corresponding to each dissociation during the titration.
Here are the key points I learned from this lesson:
- The equivalence point occurs when the moles of titrant added equals the moles of analyte. The end point is the point at which a physical indicator change occurs, which should be very close to the equivalence point.
- For strong acid-strong base titrations, the pH at the equivalence point is always 7. The titration curve shape is the same whether titrating acid or base.
- For weak acid-strong base titrations, the Henderson-Hasselbalch equation is used before and at the equivalence point to calculate pH. The titration curve shape depends on the pKa of the weak acid.
- Polyprotic
1) The document describes acid-base titration techniques, including defining terms like equivalence point and end point.
2) It discusses different types of titrations including strong acid-strong base, weak acid-strong base, and constructing titration curves.
3) Key points are made about calculating pH values before, at, and after the equivalence point for different titration scenarios. The document provides examples of constructing titration curves step-by-step.
Titration is a technique used to determine the concentration of an unknown solution by using a solution of known concentration. The known solution is called the standard solution and the unknown solution is called the sample solution. Their concentrations can be calculated using the principle of M1V1=M2V2, where M1 and V1 are the molarity and volume of the unknown solution and M2 and V2 are the molarity and volume of the known solution. In acid-base titration, an acid or base of unknown concentration is neutralized by a standard solution of base or acid. Instruments like a burette, flask, stirrer, and pipette are used. The procedure involves adding the known solution from the
1) The document discusses acid-base titration curves and determining the pH at any point during the titration of a strong acid with a strong base or a weak acid with a strong base.
2) Key aspects include calculating the equivalence point and determining the pH in four regions: before, at, and after the equivalence point as well as in the buffer region between initial addition and the equivalence point.
3) Factors that affect the titration curve include the strength of the acid and its concentration - weaker acids and more dilute solutions result in shallower curves without a clear endpoint.
This document discusses different types of titrimetry including volumetric, coulometric, and gravimetric titrimetry. It describes key concepts in titrimetric analysis including standard solutions, equivalence points, end points, titration curves, and sources of error. Specific techniques are covered such as back titration, precipitation titrimetry using silver nitrate, and different types of indicators that can be used for argentometric (silver-based) titrations including chromate, fluorescein, and iron (III). Diagrams illustrate the titration process and how curves are affected by concentration and reaction completeness.
Titration, also known as titrimetry, is a technique used to determine the concentration of an unknown solution by reacting it with a solution of known concentration. The principle of titration is based on a complete chemical reaction between the analyte and titrant. Key terms in titration include the analyte, which is the unknown solution, and the titrant, which is the standard solution of known concentration. Titration calculations rely on the law of equivalence, which states that the amount of reactants must be equivalent at the endpoint of the reaction. Titration is used in various fields such as agriculture, oil industry, chemical industry, pharmaceuticals, and food industry due to its accuracy, precision, and cost effectiveness.
1. The document discusses different types of standard solutions used in volumetric analysis, including primary and secondary standards.
2. It describes the principles and process of titration, including the use of indicators to determine the endpoint. Common types of titrations like acid-base and redox titrations are explained.
3. Examples of calculations involving titration are provided, focusing on acid-base titrations. Different types of calculations are classified, including those using normality, molarity, or mass instead of normality.
Here are the key points I learned from this lesson:
- The equivalence point occurs when the moles of titrant added equals the moles of analyte. The end point is the point at which a physical indicator change occurs, which should be very close to the equivalence point.
- For strong acid-strong base titrations, the pH at the equivalence point is always 7. The titration curve shape is the same whether titrating acid or base.
- For weak acid-strong base titrations, the Henderson-Hasselbalch equation is used before and at the equivalence point to calculate pH. The titration curve shape depends on the pKa of the weak acid.
- Polyprotic
1) The document describes acid-base titration techniques, including defining terms like equivalence point and end point.
2) It discusses different types of titrations including strong acid-strong base, weak acid-strong base, and constructing titration curves.
3) Key points are made about calculating pH values before, at, and after the equivalence point for different titration scenarios. The document provides examples of constructing titration curves step-by-step.
Titration is a technique used to determine the concentration of an unknown solution by using a solution of known concentration. The known solution is called the standard solution and the unknown solution is called the sample solution. Their concentrations can be calculated using the principle of M1V1=M2V2, where M1 and V1 are the molarity and volume of the unknown solution and M2 and V2 are the molarity and volume of the known solution. In acid-base titration, an acid or base of unknown concentration is neutralized by a standard solution of base or acid. Instruments like a burette, flask, stirrer, and pipette are used. The procedure involves adding the known solution from the
1) The document discusses acid-base titration curves and determining the pH at any point during the titration of a strong acid with a strong base or a weak acid with a strong base.
2) Key aspects include calculating the equivalence point and determining the pH in four regions: before, at, and after the equivalence point as well as in the buffer region between initial addition and the equivalence point.
3) Factors that affect the titration curve include the strength of the acid and its concentration - weaker acids and more dilute solutions result in shallower curves without a clear endpoint.
This document discusses different types of titrimetry including volumetric, coulometric, and gravimetric titrimetry. It describes key concepts in titrimetric analysis including standard solutions, equivalence points, end points, titration curves, and sources of error. Specific techniques are covered such as back titration, precipitation titrimetry using silver nitrate, and different types of indicators that can be used for argentometric (silver-based) titrations including chromate, fluorescein, and iron (III). Diagrams illustrate the titration process and how curves are affected by concentration and reaction completeness.
Titration, also known as titrimetry, is a technique used to determine the concentration of an unknown solution by reacting it with a solution of known concentration. The principle of titration is based on a complete chemical reaction between the analyte and titrant. Key terms in titration include the analyte, which is the unknown solution, and the titrant, which is the standard solution of known concentration. Titration calculations rely on the law of equivalence, which states that the amount of reactants must be equivalent at the endpoint of the reaction. Titration is used in various fields such as agriculture, oil industry, chemical industry, pharmaceuticals, and food industry due to its accuracy, precision, and cost effectiveness.
1. The document discusses different types of standard solutions used in volumetric analysis, including primary and secondary standards.
2. It describes the principles and process of titration, including the use of indicators to determine the endpoint. Common types of titrations like acid-base and redox titrations are explained.
3. Examples of calculations involving titration are provided, focusing on acid-base titrations. Different types of calculations are classified, including those using normality, molarity, or mass instead of normality.
Volumetric Analysis ( Titrimetric analysis) or TitrationAman Kakne
Volumetric analysis, also known as titrimetric analysis, is a quantitative analysis technique that determines the concentration of an unknown substance by titrating it with a solution of known concentration. The key steps are: (1) adding a known volume of the titrant of known concentration to the titrate of unknown concentration until the endpoint is reached, as indicated by a pH indicator; (2) recording the titrant volume used; and (3) calculating the concentration of the titrate based on the reaction stoichiometry and volumes added. Common types of titrations include acid-base titrations, redox titrations, and precipitation titrations. Proper indicator selection based on the relative acid/base strengths is
The document discusses different types of titrations including acid-base, oxidation-reduction, complex formation, and precipitation reactions. It defines key terms like indicator, equivalence point, and endpoint. Examples are provided for calculating concentration using titration data from reactions like acid-base titrations for chloride in urine and carbon monoxide determination. Steps are outlined for the Kjeldahl method to determine nitrogen content through acid digestion and titration.
Titration, also known as titrimetry, is a technique used to determine the concentration of an unknown solution by reacting it with a solution of known concentration. The principle is that a titrant of known concentration is added from a burette to the analyte until the chemical reaction between them is complete. Titration relies on acid-base, precipitation, complexometric, or redox reactions and is indicated by color changes from an indicator. It is a widely used analytical technique due to its accuracy, speed, low cost, and simplicity.
This document discusses acid-base titration and provides examples. It explains that acid-base titration is used to calculate the concentration of an acid or base of a known volume. It describes the setup and process for titrating an acid with a base, including using an indicator that changes color at the endpoint. Sample problems are worked through to calculate the concentration of an unknown acid or base by determining the moles of titrant used and applying stoichiometry to the balanced reaction.
* HCl is a strong acid and will titrate first
* Its equivalence point was at 35.00 mL of NaOH
* NaOH concentration is 0.100 M
* Moles of NaOH used = Volume x Concentration
= 0.03500 L x 0.100 mol/L = 0.003500 mol
* Moles of HCl = Moles of NaOH used = 0.003500 mol
* H3PO4 is a weak acid and will titrate second
* Its equivalence point was at 50.00 mL of NaOH
* Additional NaOH used = 50.00 mL - 35.00 mL = 15.00 mL
* Moles of additional Na
Titration is a technique used to determine the concentration of an unknown substance by reacting it with a known quantity of a titrant. The equivalence point occurs when stoichiometric amounts of the reactants have reacted. An indicator is used to identify the endpoint, which may differ from the equivalence point. The pH at the equivalence point provides information about whether a strong acid/base or weak acid/base reaction took place.
This document discusses acid-base titration, including definitions of acids and bases, strong vs weak acids and bases, and the technique of titration. It explains that a titration reaches the equivalence point when the moles of acid equals the moles of base, producing a neutral solution. This can be shown using the equation MAVA = MBVB, where M is molarity, V is volume, and A and B indicate acid and base. An example titration calculation is provided.
This document provides information and examples on solutions and titrations in chemistry:
- It defines key terms like solute, solvent, concentration, molarity and explains how to calculate concentrations in g/dm3 and moldm-3.
- Examples are given for calculating the mass of a solute needed to make a solution of a given volume and molarity, and for calculating concentrations when solutions are diluted.
- A titration is described as a procedure using a burette to add one solution of known concentration to a flask of another until reaction is complete.
- Standard solutions that are suitable for titrations are outlined.
- Worked examples of titration calculations include determining
Chapter 16.1 and 2 : Acid-Base Titrations and pHChris Foltz
The document discusses acid-base titrations and pH. It defines pH as the negative logarithm of hydronium ion concentration and explains how to calculate pH from [H3O+] and vice versa. It also describes how to perform and calculate molarity from a titration experiment by determining moles of acid/base reacted using volume and molarity of the titrant. Sample titration problems are worked through demonstrating these concepts.
This document discusses different types of titrations used in analytical chemistry. It describes four main types: acid-base titrations, complexometric titrations, precipitation titrations, and redox titrations. It provides examples of each type, including EDTA titrations used for complexometric titrations to determine hardness, Mohr's method for precipitation titration of chloride ions, and titration of iron using potassium dichromate for redox titrations. The document also covers topics like concentration systems, including definitions and calculations involving molarity, molality, formality, and normality.
1. The document describes acid-base titrations involving strong acids and bases as well as weak acids and bases. Titrations result in titration curves that can be divided into regions based on the relative amounts of acid and base present.
2. Key regions include before equivalence, at equivalence, and after equivalence. The pH at equivalence depends on whether the acid or base is strong or weak. Indicators are used to detect the equivalence point based on their color change near the desired pH.
3. Calculations are provided to determine pH in each region based on acid or base strength, volumes reacted, and equilibrium constants. Assumptions made in the calculations must be checked for validity.
This document provides an introduction to chemistry laboratory analysis. It discusses different types of analysis including qualitative analysis to identify substances and quantitative analysis to determine amounts. Key terms in volumetric analysis like titration, titrant, and endpoint are explained. Different types of titrations such as acid-base, redox, complexometric, and precipitation titrations are described. Factors that affect accuracy and precision in analysis are covered. The roles and selection of various indicators for different types of titrations are also summarized.
The document describes a titration experiment involving:
1) Standardizing a sodium hydroxide solution by titrating it against samples of potassium hydrogen phthalate and calculating the molarity of the NaOH.
2) Titrating samples of vinegar with the standardized NaOH solution and calculating the molarity and percentage by mass of acetic acid in the vinegar.
3) The titrations used phenolphthalein indicator and were conducted using common lab equipment like a burette, pipette, and Erlenmeyer flasks. Calculations applied the principles of titration stoichiometry and acid-base reactions.
Titration - principle, working and applicationSaloni Shroff
A brief introduction to the titration technique used to know the concentration of unknown solutions. different types, indicators used and its application in foods and nutrition is also described.
Volumetric Analysis
Types of titration
Acid- Base Theory
Reaction, End Point & Indicators
Acid- Base titration
Titration curve
Non- Aqueous Titration
Precipitation Titration
Complexometric Titration
Oxidation- Reduction Titration,
Calculation. Errors
General Informations,
The document summarizes an experiment on acid-base titrations. Sodium hydroxide was standardized and used to titrate hydrochloric acid, phosphoric acid, and an unknown acid. Titrations of hydrochloric acid showed the equivalence point was pH 7. Phosphoric acid titration showed two equivalence points, determining its two pKa values. Titration of the unknown acid found its molecular weight to be 76.09 g/mol, identifying it as tartaric acid. A final potassium hydrogen phthalate titration found the experimental curve nearly identical to the theoretical curve.
Titration is a procedure to determine the volume of an acid and base solution needed to exactly neutralize each other. By using a standard solution of known concentration, the concentration of another solution can be determined. There are three types of acid-base titrations: strong acid-strong base, strong acid-weak base, and weak acid-strong base titration. The titration curve shows the pH changes at different volumes of titrant added and the suitable indicators correspond to the end point pH range of each titration type.
This document discusses titrimetric analysis, which involves determining the concentration of an unknown substance by titrating it with a standard solution of known concentration. Specifically, it describes different types of titrations including acid-base titrations using pH indicators, redox titrations using redox indicators or color changes, and complexometric titrations using specialized indicators. It also discusses various techniques for determining the endpoint of a titration, such as using indicators, potentiometers, conductivity, spectroscopy, or precipitation.
The document discusses volumetric analysis techniques for determining the concentration of acids and bases through titration. It provides examples of calculating molarity from moles and volume. An experiment is described where students determine the concentration of an unknown sodium hydroxide solution by titrating it with hydrochloric acid of a known concentration.
NCHE 211 UNIT 2 VOLUMETRY and Complexometry titration.pdfKagisoEagle
This module consists of six study units that are further divided into study sections. The study units include basic concepts, volumetry, gravimetry, surface characterization, atomic spectrometry, and separation methods. The document then provides an overview of analytical chemistry and its branches, classification of quantitative analysis methods, and learning outcomes related to volumetric analysis and titrations. [/SUMMARY]
This document discusses acid-base titrations. It defines key terms like titration, equivalence point, end point, indicators, and standard solutions. It explains different types of titrations including strong acid-strong base, weak acid-strong base, and diprotic systems. Graphs of titration curves are shown for different systems. Methods for determining the endpoint are described, including using indicators, derivatives of the titration curve, and the Gran method. Common acid-base indicators and standard solutions used in titrations are also outlined.
Volumetric Analysis ( Titrimetric analysis) or TitrationAman Kakne
Volumetric analysis, also known as titrimetric analysis, is a quantitative analysis technique that determines the concentration of an unknown substance by titrating it with a solution of known concentration. The key steps are: (1) adding a known volume of the titrant of known concentration to the titrate of unknown concentration until the endpoint is reached, as indicated by a pH indicator; (2) recording the titrant volume used; and (3) calculating the concentration of the titrate based on the reaction stoichiometry and volumes added. Common types of titrations include acid-base titrations, redox titrations, and precipitation titrations. Proper indicator selection based on the relative acid/base strengths is
The document discusses different types of titrations including acid-base, oxidation-reduction, complex formation, and precipitation reactions. It defines key terms like indicator, equivalence point, and endpoint. Examples are provided for calculating concentration using titration data from reactions like acid-base titrations for chloride in urine and carbon monoxide determination. Steps are outlined for the Kjeldahl method to determine nitrogen content through acid digestion and titration.
Titration, also known as titrimetry, is a technique used to determine the concentration of an unknown solution by reacting it with a solution of known concentration. The principle is that a titrant of known concentration is added from a burette to the analyte until the chemical reaction between them is complete. Titration relies on acid-base, precipitation, complexometric, or redox reactions and is indicated by color changes from an indicator. It is a widely used analytical technique due to its accuracy, speed, low cost, and simplicity.
This document discusses acid-base titration and provides examples. It explains that acid-base titration is used to calculate the concentration of an acid or base of a known volume. It describes the setup and process for titrating an acid with a base, including using an indicator that changes color at the endpoint. Sample problems are worked through to calculate the concentration of an unknown acid or base by determining the moles of titrant used and applying stoichiometry to the balanced reaction.
* HCl is a strong acid and will titrate first
* Its equivalence point was at 35.00 mL of NaOH
* NaOH concentration is 0.100 M
* Moles of NaOH used = Volume x Concentration
= 0.03500 L x 0.100 mol/L = 0.003500 mol
* Moles of HCl = Moles of NaOH used = 0.003500 mol
* H3PO4 is a weak acid and will titrate second
* Its equivalence point was at 50.00 mL of NaOH
* Additional NaOH used = 50.00 mL - 35.00 mL = 15.00 mL
* Moles of additional Na
Titration is a technique used to determine the concentration of an unknown substance by reacting it with a known quantity of a titrant. The equivalence point occurs when stoichiometric amounts of the reactants have reacted. An indicator is used to identify the endpoint, which may differ from the equivalence point. The pH at the equivalence point provides information about whether a strong acid/base or weak acid/base reaction took place.
This document discusses acid-base titration, including definitions of acids and bases, strong vs weak acids and bases, and the technique of titration. It explains that a titration reaches the equivalence point when the moles of acid equals the moles of base, producing a neutral solution. This can be shown using the equation MAVA = MBVB, where M is molarity, V is volume, and A and B indicate acid and base. An example titration calculation is provided.
This document provides information and examples on solutions and titrations in chemistry:
- It defines key terms like solute, solvent, concentration, molarity and explains how to calculate concentrations in g/dm3 and moldm-3.
- Examples are given for calculating the mass of a solute needed to make a solution of a given volume and molarity, and for calculating concentrations when solutions are diluted.
- A titration is described as a procedure using a burette to add one solution of known concentration to a flask of another until reaction is complete.
- Standard solutions that are suitable for titrations are outlined.
- Worked examples of titration calculations include determining
Chapter 16.1 and 2 : Acid-Base Titrations and pHChris Foltz
The document discusses acid-base titrations and pH. It defines pH as the negative logarithm of hydronium ion concentration and explains how to calculate pH from [H3O+] and vice versa. It also describes how to perform and calculate molarity from a titration experiment by determining moles of acid/base reacted using volume and molarity of the titrant. Sample titration problems are worked through demonstrating these concepts.
This document discusses different types of titrations used in analytical chemistry. It describes four main types: acid-base titrations, complexometric titrations, precipitation titrations, and redox titrations. It provides examples of each type, including EDTA titrations used for complexometric titrations to determine hardness, Mohr's method for precipitation titration of chloride ions, and titration of iron using potassium dichromate for redox titrations. The document also covers topics like concentration systems, including definitions and calculations involving molarity, molality, formality, and normality.
1. The document describes acid-base titrations involving strong acids and bases as well as weak acids and bases. Titrations result in titration curves that can be divided into regions based on the relative amounts of acid and base present.
2. Key regions include before equivalence, at equivalence, and after equivalence. The pH at equivalence depends on whether the acid or base is strong or weak. Indicators are used to detect the equivalence point based on their color change near the desired pH.
3. Calculations are provided to determine pH in each region based on acid or base strength, volumes reacted, and equilibrium constants. Assumptions made in the calculations must be checked for validity.
This document provides an introduction to chemistry laboratory analysis. It discusses different types of analysis including qualitative analysis to identify substances and quantitative analysis to determine amounts. Key terms in volumetric analysis like titration, titrant, and endpoint are explained. Different types of titrations such as acid-base, redox, complexometric, and precipitation titrations are described. Factors that affect accuracy and precision in analysis are covered. The roles and selection of various indicators for different types of titrations are also summarized.
The document describes a titration experiment involving:
1) Standardizing a sodium hydroxide solution by titrating it against samples of potassium hydrogen phthalate and calculating the molarity of the NaOH.
2) Titrating samples of vinegar with the standardized NaOH solution and calculating the molarity and percentage by mass of acetic acid in the vinegar.
3) The titrations used phenolphthalein indicator and were conducted using common lab equipment like a burette, pipette, and Erlenmeyer flasks. Calculations applied the principles of titration stoichiometry and acid-base reactions.
Titration - principle, working and applicationSaloni Shroff
A brief introduction to the titration technique used to know the concentration of unknown solutions. different types, indicators used and its application in foods and nutrition is also described.
Volumetric Analysis
Types of titration
Acid- Base Theory
Reaction, End Point & Indicators
Acid- Base titration
Titration curve
Non- Aqueous Titration
Precipitation Titration
Complexometric Titration
Oxidation- Reduction Titration,
Calculation. Errors
General Informations,
The document summarizes an experiment on acid-base titrations. Sodium hydroxide was standardized and used to titrate hydrochloric acid, phosphoric acid, and an unknown acid. Titrations of hydrochloric acid showed the equivalence point was pH 7. Phosphoric acid titration showed two equivalence points, determining its two pKa values. Titration of the unknown acid found its molecular weight to be 76.09 g/mol, identifying it as tartaric acid. A final potassium hydrogen phthalate titration found the experimental curve nearly identical to the theoretical curve.
Titration is a procedure to determine the volume of an acid and base solution needed to exactly neutralize each other. By using a standard solution of known concentration, the concentration of another solution can be determined. There are three types of acid-base titrations: strong acid-strong base, strong acid-weak base, and weak acid-strong base titration. The titration curve shows the pH changes at different volumes of titrant added and the suitable indicators correspond to the end point pH range of each titration type.
This document discusses titrimetric analysis, which involves determining the concentration of an unknown substance by titrating it with a standard solution of known concentration. Specifically, it describes different types of titrations including acid-base titrations using pH indicators, redox titrations using redox indicators or color changes, and complexometric titrations using specialized indicators. It also discusses various techniques for determining the endpoint of a titration, such as using indicators, potentiometers, conductivity, spectroscopy, or precipitation.
The document discusses volumetric analysis techniques for determining the concentration of acids and bases through titration. It provides examples of calculating molarity from moles and volume. An experiment is described where students determine the concentration of an unknown sodium hydroxide solution by titrating it with hydrochloric acid of a known concentration.
NCHE 211 UNIT 2 VOLUMETRY and Complexometry titration.pdfKagisoEagle
This module consists of six study units that are further divided into study sections. The study units include basic concepts, volumetry, gravimetry, surface characterization, atomic spectrometry, and separation methods. The document then provides an overview of analytical chemistry and its branches, classification of quantitative analysis methods, and learning outcomes related to volumetric analysis and titrations. [/SUMMARY]
This document discusses acid-base titrations. It defines key terms like titration, equivalence point, end point, indicators, and standard solutions. It explains different types of titrations including strong acid-strong base, weak acid-strong base, and diprotic systems. Graphs of titration curves are shown for different systems. Methods for determining the endpoint are described, including using indicators, derivatives of the titration curve, and the Gran method. Common acid-base indicators and standard solutions used in titrations are also outlined.
This document discusses acid-base equilibria and calculations involving pH. It defines Bronsted-Lowry acids and bases as substances that can donate or accept protons. It describes how to calculate the pH of strong acids, strong bases, weak acids and buffer solutions. It also covers acid-base indicators, and titration curves for strong vs weak acids and bases.
This document provides information on volumetric analysis, specifically volumetric titration. It begins by defining volumetric analysis as a quantitative chemical analysis method that involves measuring the volumes of reacting substances. A titration procedure is described where a solution of known concentration is added from a burette to a solution containing an unknown concentration of analyte until the equivalence point is reached. The summary discusses the key components of titration including the titrant, titrand, and indicator used to detect the endpoint. Common types of titrations like acid-base, precipitation, and complexometric titrations are also mentioned.
This document discusses acid-base titrations and buffer solutions. It begins by defining acid and base dissociation constants (Ka and Kb). It then discusses amphiprotic substances, solvent effects, and the autoionization of water. Next, it covers acid-base titration curves including types of curves and calculations at different points in the titration. It discusses titration of strong acids with strong bases and vice versa. Finally, it defines buffer solutions and the Henderson-Hasselbalch equation. It provides examples of calculating the pH of buffer solutions and how buffers resist pH changes upon dilution or addition of acids and bases.
This document discusses acid-base theories and equilibria in water. It describes the Arrhenius, Bronsted-Lowry, and Lewis theories of acids and bases. The autoionization of water and definitions of pH and pOH are explained. Calculations of pH for strong/weak acids and bases, salts, and buffer solutions using the ionization constant and Henderson-Hasselbalch equation are presented with examples. The role of buffers in resisting pH change upon addition of acids or bases is also summarized.
1. The document discusses Brønsted-Lowry acids and bases, including strong and weak acids and bases. Strong acids and bases completely dissociate in water, while weak ones only partially dissociate.
2. Examples of calculations involving titration reactions are shown, including determining the pH and volume of base needed to neutralize an acid. The autoionization of water and acid/conjugate base pairs are also covered.
3. Buffers are discussed as mixtures of a weak acid and its conjugate base that resist changes to pH when acids or bases are added. The pH of a buffer solution is close to the pKa of the acid/base pair.
This document discusses volumetric (titrimetric) methods of analysis. It begins by reviewing important concepts such as acid/base definitions, pH calculations, and titration terms. It then describes the four main types of titrimetric methods and provides examples. The rest of the document focuses on acid-base titrations, explaining terms like equivalence point and end point. It discusses indicators and how to select them based on titration curves. It also provides examples of calculating titration curves for strong acid-strong base reactions to determine pH values at different points in the titration.
This document summarizes key concepts about acids and bases:
- It describes three theories of acids and bases: Arrhenius, Brønsted-Lowry, and Lewis.
- It explains the pH scale and relationships between pH, pOH, and ionic product of water.
- It discusses strong vs. weak acids/bases and how their dissociation constants relate to acid/base strength.
- It provides examples of titration curves and how buffers maintain pH.
1. Analytical chemistry methods can be categorized based on sample size, extent of determination, and nature of analytical methods. Common quantitative analytical methods include acid-base titrations, redox titrations, and gravimetric analysis.
2. Acid-base titrations involve neutralizing an acid or base of unknown concentration with a standard solution of known concentration. Indicators are used to detect the endpoint.
3. Titration curves can be used to determine the equivalence point and pH at the equivalence point for different acid-base strength combinations. Standardization is required to determine the exact concentration of titrants used in titrations.
1) The document discusses volumetric analysis, which is a quantitative chemical analysis method that involves titration. It is defined as determining the concentration of an unknown solution by titrating a known volume of it with a solution of known concentration.
2) Key terms in volumetric analysis are discussed, including titration, titrant, equivalence point, indicator, end point, and titration error.
3) Requirements for volumetric analysis are that the reaction must be complete, stoichiometric, relatively fast, and have a detectable physical or chemical change at the equivalence point that can be identified using an indicator.
Acid-base titration is a quantitative analysis technique used to determine the concentration of an acid or base. It involves titrating a solution of known concentration (the titrant) with the analyte solution until the equivalence point is reached. The equivalence point occurs when the moles of H3O+ and OH- are equal. The pH at the equivalence point depends on whether the acid and base are strong or weak. Indicators are used to visually determine the endpoint of the titration based on a color change at the appropriate pH. Common applications of titration include determining active ingredients in pharmaceuticals and chemicals and measuring water quality parameters.
A buffer is a solution of a weak acid and its conjugate base (salt) that resists changes in pH in both directions—either up or down, when small quantities of an acid and a base(alkali) are added to it.
This document provides an overview of acid-base titration and summarizes the key steps and considerations when performing a titration. It discusses selecting an appropriate indicator based on the relative strengths of the acid and base, performing multiple titrations to determine the endpoint accurately, and calculating pH at different points during the titration, including the initial pH, pH before and at the equivalence point, and pH after the equivalence point. Formulas are provided for calculating pH at these different stages of a titration, whether it involves a strong acid-strong base, strong acid-weak base, or weak acid-strong base reaction.
This document discusses acids and bases, including titration curves, pH, strong vs weak acids/bases, and calculations involving titrations and buffers. It provides information on key terms like equivalence point, acid and base dissociation constants, and how to set up and solve titration problems. Examples are given of titration calculations and the common ion effect on buffer solutions. Concepts covered include pH measurements, indicator selection, and how buffers resist pH changes upon addition of acids or bases.
Acids bases and buffers
Pharmaceutical Inorganic Chemistry
Unit 2, Chapter 1
Arrhenius, Bronsted-Lowry and Lewis Concepts of Acids and bases,
Concept of pH, pOH, pKa, pKb
Concept of buffers, buffer solutions, buffer action, and buffer capacity,
Buffer equation
Buffers in pharmaceuticals
Buffered isotonic solutions
Measurement and adjustment of tonicity
1. The document summarizes key concepts about acids and bases from Chapter 8, including the Arrhenius and Brønsted-Lowry theories of acids and bases. It defines acids as proton donors and bases as proton acceptors.
2. The pH scale is introduced as a measurement from 0 to 14 that indicates the acidity or basicity of a solution. The pH is defined as the negative log of the hydronium ion concentration.
3. Neutralization reactions between acids and bases are discussed, producing a salt and water. The net ionic equation is written as the reaction between hydronium and hydroxide ions.
Mrs. Poonam Sunil Aher discusses different analytical techniques including quantitative methods like solubility, melting point, and boiling point as well as qualitative methods like color, odor, and identification tests. She focuses on titrimetric techniques like acid-base titration using indicators, redox titration, iodimetry titration using starch, and precipitation titration. She also covers gravimetric analysis techniques like volatilization and precipitation, and discusses aqueous versus non-aqueous titration.
1. STK1094 Analytical Chemistry 1
Dayang Norafizan binti Awang Chee
Faculty of Resource Science and Technology
Universiti Malaysia Sarawak
This OpenCourseWare@UNIMAS and its related course materials are licensed under
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2. Learning Objectives
At the end of this lesson, students should be able to:
Describe the difference between an “endpoint” and an
“equivalence point” in an acid-base titration
Identify the equivalence point in an acid-base titration
from the pH titration curve
Illustrate titration of a weak acid with a strong base.
3. Defining Terms
• Standard solution: A reagent of a known concentration which used in
the titrimetric analysis
• Titration: This is performed by adding a standard solution from burette
or other liquid-dispensing device to a solution of the analyte until the
point at which the reaction is believe to be completed
• Equivalence point: Occurs in a titration at the point in which the
amount of added titrant is chemically equivalent to the amount of
analyte in a sample
• Back-titration: This is a process in which an excess of the standard
titrant is added, and the amount of the excess is determined by back
titration with a second standard titrant.
In this instance, the equivalent point corresponds with the amount of
initial titrant is chemically equivalent to the amount of analyte plus the
amount of back titrant.
4. Defining Terms
• End point: The point in titration when a physical change occurs that is
associated with the condition of chemical equivalence
• Indicators are used to give an observable physical change (end point)
or at near the equivalence point by adding them to the analyte. The
difference between end point and equivalence point should be very
small and this difference is referred to as titration error.
• Titration error, Et
Et=Vep – Veq
Vep is the actual volume used to get to the end point.
Veq is the theoretical value of reagent required to reach the end point.
5. 5
Acid-Base Titrations
• A quick and accurate method for determining acidic
or basic substances in many samples.
• The titrant is typically a strong acid or base.
• The sample species can be either a strong or weak
acid or base.
6. 6
Acid-Base Titration
Types of acid-base titrations:
1)strong acid – strong base titration
2)weak acid – strong base titration
3)strong acid – weak base titration
4) polyprotic acid – strong base titration
5) polybasic base – strong acid titration
7. 7
Strong Acid - Strong Base Titration
In strong acid – strong base titration, there are three
regions of the titration curve that represent different kinds
of calculations :
- before equivalence point
- at equivalence point
- after equivalence point
8. Titration curve
Strong acid titrated with a strong base:
• The net reaction is
H3O++ OH- → 2H2O
• Before the equivalence point, acid is present in excess
• pH is determined by the concentration of excess HCl
[𝐻3 𝑂+
] =
𝑚𝑚𝑜𝑙𝑒𝑠 𝑎𝑐𝑖𝑑−𝑚𝑚𝑜𝑙𝑒𝑠 𝑏𝑎𝑠𝑒
𝑡𝑜𝑡𝑎𝑙 𝑣𝑜𝑙𝑢𝑚𝑒
8
9. Strong acid titrated with a strong base
• At equivalence point, moles of acid and moles of base are
equal.
• At equivalence point,
[H3O+] = [OH- ]
pKw = 14 = pH + pOH
pH = 7
• So, the equivalence point for strong acid/base is always a
pH=7
9
10. Strong acid titrated with a strong base
Overtitration
Pass the equivalence point, we don’t have any acid remaining. All that we are doing
is diluting our titrant.
[𝑶𝑯−
] =
𝒎𝒎𝒐𝒍𝒆𝒔 𝒆𝒙𝒄𝒆𝒔𝒔
𝒕𝒐𝒕𝒂𝒍 𝒗𝒐𝒍𝒖𝒎𝒆
pH = 14-pOH
Eg. Construct a titration curve for the titration of 100 mL 0.1 M HCl with 0.1 M NaOH
1) Volume of NaOH needed to reach eq. point
Moles HCl = moles NaOH
VNaOH = 100.0 mL
2) Before addition of NaOH
pH = - log [0.1] = 1
3) After addition of 10mL NaOH
[𝐻3 𝑂+] =
100 𝑚𝑙 0.10𝑀 −(10𝑚𝑙)(0.10𝑀)
100 𝑚𝑙+10 𝑚𝑙
= 0.082 M, pH= 1.09
10
12. Titration curve
4) At equivalence point
• Equivalence point, moles of
HCl= moles of NaOH
• Since neither is in excess, pH is
determined by Kw
Kw = 1.00 x 10-14 =
[H3O+][OH-] = [H3O+]2
[H3O+] = 1.00 x 10-7
pH= 7
• Note that for the first 90 mL of
titration, pH = 2.28
• At eq. point, the pH value jump
of 4.72 pH unit
12
13. Titration curve
5) Overtitration
• Account for the dilution of titrant
• 10 mL overtitration
[OH-] = moles excess NaOH = MVNaOH- MVHCl
Vtotal
= (0.1M)(110mL)-(0.1M)(100mL)
210 mL
= 0.0048M
pOH = 2.32
pH = 14-2.32 = 11.68
13
15. Titration curve
Titration of a strong base with a
strong acid:
• If we plot pOH rather than pH,
the result still look identical.
• Typically, we still plot pH verses
mL titrant, so the curve is
inverted.
15
16. Titration of weak acids & weak bases with
strong titrant
• Must concerned with conjugate acid/base pairs & their
equilibrium
16
17. Titration of weak acids & weak bases with
strong titrant
Before titration:
• If the sample is weak acid, then use
• 𝐾𝐴=
𝐻3 𝑂+ [𝐴−]
[𝐻𝐴]
• [H3O+]=[A-]
• Calculate the pH value
17
• If the sample is weak base, then use
• 𝐾 𝐵=
𝑂𝐻− [𝐻𝐴−]
[𝐴−]
• [OH-]=[HA]
• Calculate the pH value = 14 - pOH
18. Titration of weak acids & weak bases
with strong titrant
Before equivalence point:
• Equilibrium expression used is the Henderson-
Hasselbalch equation
• Starting with an acid
• pH= 𝑝𝐾 𝐴 + log
[𝐴−]
[𝐻𝐴]
• Starting with base
• pH= 14 − (𝑝𝐾 𝐵 + log
[𝐻𝐴]
[𝐴−]
)
18
19. Titration of weak acids & weak bases
with strong titrant
At equivalence point
• All sample is converted to its conjugate form
• If the sample was an acid-solve the pH using KB
relationship
• If the sample was a base-solve the pH using KA
relationship
𝐾 𝐵+ 𝐾𝐴= 14
19
20. Titration of weak acids & weak bases with
strong titrant
Overtitration:
• Identical to strong acid/strong base example.
• Need to account for the amount of excess titrant & how much it
has been diluted.
• Eg. 100 mL solution of 0.1 M benzoic acid is titrated with 0.1 M
NaOH. Construct a titration curve.
For benzoic acid
Ka=6.31 x 10-5
pKa=4.20
1) Volume of NaOH needed to reach eq. point
Moles C5H6COOH = moles NaOH
VNaOH = 100.0 mL
20
21. Titration of weak acids & weak bases with
strong titrant
2) Before titration:
• 𝐾𝐴=
𝐻3 𝑂+ [𝐴−]
[𝐻𝐴]
• [𝐻3 𝑂+]= [𝐴−]
• Assume [A-] is negligible compared to [HA]
𝐾𝐴= 6.31 × 10−5=
𝑥2
0.10
= 6.31 × 10−5 (0.10)
= 0.025 M
pH= 2.60
21
22. Titration of weak acids & weak bases with
strong titrant
3) After addition of 10mL NaOH
Henderson-Hasselbalch equation
pH = pKa + log [C5H6COO-]
[C5H6COOH]
[C5H6COOH] = moles unreacted C5H6COOH = MVC5H6COOH- MVNaOH
Vtotal Vtotal
= (0.1M)(100mL)-(0.1M)(10mL)
110 mL
= 0.082M
[C5H6COO-] = moles NaOH added = MVNaOH
Vtotal Vtotal
= (0.1M)(10mL)
110 mL
= 0.009M
pH = 4.2 + log (0.009/0.082) = 3.24
• Calculate other point by repeating this process
22
23. Titration of weak acids & weak bases with
strong titrant
23
mL
titrant
pH
0 2.60
10 3.24
20 3.60
30 3.83
40 4.02
50 4.20
60 4.38
70 4.57
80 4.80
90 5.15
mL titrant
24. Titration of weak acids & weak bases with
strong titrant
4) At equivalence point
100mL titrant:
• All acid has been converted to its conjugate base – benzoate
• Use KB relationship.
• 𝐾 𝐵=
[𝑂𝐻−][𝐻𝐴]
[𝐴−]
• 𝐾 𝐵= 𝐾 𝑊/𝐾𝐴= 1.58 × 10−10
n benzoic acid = n NaOH
• Predominate ion in solution is A-, which is a weak base
[A-] = moles acid/ total volume = 0.05M
• We have diluted the sample & the total volume at this point is 200 mL.
• We can assume that [benzoic acid] is negligible compared to [benzoate].
24
25. Titration of weak acids & weak bases with
strong titrant
4) At equivalence point
C5H6COO- (aq) + H2O (l) OH- (aq) + C5H6COOH
𝐾𝑏= 1.58 × 10−10
=
𝑥2
0.050
𝑥 = (1.58 × 10−10)(0.050)
25
mL titrant
26. Titration of weak acids or weak bases with
strong titrant
5) Overtitration
• Need to account for the dilution of titrant.
• Eg: 10 mL excess.
26
27. Titration of weak acids or weak bases with
strong titrant
27
mL
titrant
Total
volume
[OH-] pH
110 210 0.0048 11.68
120 220 0.0091 11.96
130 230 0.013 12.11
140 240 0.017 12.23
150 250 0.020 12.30
30. Self-Reflection
• What is the difference between end-point and
equivalence point?
• How to build the titration curve for strong
acid/strong base with weak acid/weak base
and vice versa?