Calculation of uncertainty in titrimetry Ivan Špánik
|
|
- Bruce Miles
- 5 years ago
- Views:
Transcription
1 Calculation of uncertainty in titrimetry Ivan Špánik Problem A solution of hydrochloric acid (HCl) is standardised against a solution of sodium hydroxide (NaOH). The NaOH is titrated against the titrimetric standard potassium hydrogen phthalate (KHP). It is assumed that the NaOH concentration is known to be of the order of 0.1 mol L 1. The end-point of the titration is determined by an automatic titration system using a combined ph-electrode to measure the shape of the ph-curve. Procedure Approximately g of the previously dried KHP is weighed to achieve a titration volume of 19 ml NaOH. The KHP is dissolved in 50 ml of DI water and then titrated using the NaOH solution. A titration is performed using automated burette with potentiometric indication of endpoint. 15 ml of the HCl solution is transferred by volumetric pipette. The HCl solution is diluted with de-ionised water to volume 50 ml solution in the titration vessel. The same automatic titrator performs the measurement of HCl solution. 1
2 Uncertainty sources Uncertainty model Uncertainty sources 2
3 m(khp) mass KHP Measured value of weight: g Non-linearity of the balance (declaration): ± 0.15 mg Conversion to a standard deviation using a rectangular distribution P(KHP) purity of KHP Is given by producer. He declares purity 100 % ± 0.05% We have to consider rectangular distribution Uncertainty sources 3
4 V(NaOH) Standardisation (consumption of 19 ml) Calibration: given by producer. He declares ucertainty of volume 0.03 ml. We have to consider triangular distribution Temperature: possible temperature variation is ± 4 C and is treated by rectangular distribution V(NaOH) Standardisation (consumption of 19 ml) End point detection: error can be caused by oxidation of atmospheric CO 2. Titration is performed in Argon atmosphere so no error is observed. V(NaOH) Titration (consumption of 15 ml) Calibration: given by producer. He declares ucertainty of volume 0.03 ml. We have to consider triangular distribution Temperature: possible temperature variation is ± 4 C and is treated by rectangular distribution 4
5 V(NaOH) Titration (consumption of 15 ml) End point detection: error can be caused by oxidation of atmospheric CO 2. Titration is performed in Argon atmosphere so no error is observed. Uncertainty sources M(KHP) Molecular weight sum formula: C8H5O4K Assumption: triangular distribution M KHP = g/mol 5
6 Uncertainty sources V(HCl) taken by pipette 15 ml Calibration: given by producer. He declares ucertainty of volume 0.02 ml. We have to consider triangular distribution Temperature: possible temperature variation is ± 4 C and is treated by rectangular distribution Calculation Uncertainty evaluation 6
7 Calculation Uncertainty evaluation Uncertainty evaluation Expanded uncertainty 7
8 Calculation of uncertainty in HPLC determination of caffeine in coca cola Ivan Špánik Problem A simazine is determined using HPLC. Since suggested concentrattion in waste waters is high, no sample preconcentration is required. The concentration is determined using calibration curve. Simazine Measurand: Uncertainty sources The specification of the measurand is according the SOP, DIN/ISO methods or laboratory methods. Identification of sources of uncertainty For the identification of the sources of uncertainty a cause effect diagram is very useful. From this diagram the relation between the sources of uncertainty can also be seen. 8
9 Uncertainty sources The uncertainty consists of three parts: The determination of the mass of simazine; The purity of the chemical; The measurement of volume - depends on the fabrication tolerance, the temperature and the repeatability. Uncertainty net weight of simazine According to the specification of the manufacturer of the balance the tolerance amounts to g (standard deviation). u mass = 0.1mg 9
10 Uncertainty purity of chemicals According to the specification of the manufacturer the purity amounts to 98.5% ± 1.5% (equal to ± 0.015). If a normal distribution and a confidence interval of 95% are assumed these result in u purity = 0.015/1.96 = Uncertainty volume measurement This uncertainty (100-ml graduated flask) consists of three parts: 1. Calibration by the manufacturer. According to the manufacturer s instructions the tolerance at 20 C is 100 ± 0.1 ml. With the assumption of a rectangular distribution (declared by the manufacturer) the uncertainty is Uncertainty temperature in the laboratory. If the graduated flask with the solution is not kept at 20 C the influence of temperature has to be considered. The coefficient of thermal expansion g of water amounts to 1.806x10-4 / C; therefore, With the assumption of a rectangular distribution the uncertainty is 10
11 The combined uncertainty of the volume measurement (100-ml graduated flask) is: Relative uncertainty of the stock solution and relative individual contributions: 1 stock, 2 purity, 3 mass, 4 volume. The concentration of the stock solution is: 11
12 The combined uncertainty of the stock solution is: Uncertainty sources Pipette Analogous to volumetric flask: 12
13 Uncertainty sources Calibration curve Five concentrations (125, 250, 350, 500, 600 mg/l) were used, each solution was injected three times. The result of the linear regression is Y= R= Uncertainty is expressed as uncertainty of slope and intercept Total combined uncertainty 13
14 Expanded uncertainty Expanded uncertainty A coverage factor k =2 is selected: U expanded = 2 x 13.5 = 27 mg/l Presence of Simazine equals to (500 ± 27) mg/l Uncertainty Relative uncertainty of the stock solution and relative individual contributions: 1 total, 2 stock, 3 pipette, 4 calibration curve 14
CHEM 30A EXPERIMENT 8 & 9: ACID- BASE TITRATION. Learning Outcomes. Introduction. Upon completion of this lab, the student will be able to:
1 Learning Outcomes CHEM 30A EXPERIMENT 8 & 9: ACID- BASE TITRATION Upon completion of this lab, the student will be able to: 1) Prepare a solution of primary standard 2) Determine the molar concentration
More informationChemistry 143 Experiment #11 Acid Base Titration Dr. Caddell. Titrating Acid
Titrating Acid In this lab you will first determine the concentration of sodium hydroxide in a stock solution that you prepare. You will then use that stock sodium hydroxide solution to titrate a solution
More informationChemistry Determination of Mixed Acids
Chemistry 3200 Acid-base titration is one of the most common operations in analytical chemistry. A solution containing an unknown amount of ionizable hydrogen can be titrated with a solution of standard
More informationChemistry 143 Acid Base Titration Dr. Caddell. Titrating Acid
Titrating Acid In this lab you will first determine the concentration of sodium hydroxide in a stock solution that you prepare. You will then use that stock sodium hydroxide solution to titrate a solution
More informationUnit 3 Chemistry - Volumetric Analysis
Unit 3 Chemistry Volumetric Analysis Volumetric analysis is a quantitative chemical analysis used to determine the unknown concentration of one reactant [the analyte] by measuring the volume of another
More informationEXPERIMENT A7: VINEGAR TITRATION. Learning Outcomes. Introduction. Upon completion of this lab, the student will be able to:
1 Learning Outcomes EXPERIMENT A7: VINEGAR TITRATION Upon completion of this lab, the student will be able to: 1) Prepare a solution of primary standard 2) Determine the molar concentration of a solution
More informationVolumetric Analysis: Acids & Bases OL
Name: Volumetric Analysis 1. Concentrations of Solutions Objectives -define solution -define concentration -define molarity -express concentration of solutions in mol/l(molarity), g/l and also in % (v/v)
More informationChapter 9. Volumetric Analysis
Chapter 9 Volumetric Analysis The terms volumetric analysis, titrimetry and titration are used interchangeably to describe a procedure which analyses chemicals in solution by accurate volume measurement.
More informationPartner: Alisa 1 March Preparation and Properties of Buffer Solutions
Partner: Alisa 1 March 2012 Preparation and Properties of Buffer Solutions Purpose: The purpose of this experiment is to compare the ph effect on buffered and non-buffered solutions as well as making a
More informationMolarity of Acetic Acid in Vinegar A Titration Experiment
Molarity of Acetic Acid in Vinegar A Titration Experiment Introduction Vinegar is prepared commercially in two steps, both requiring microorganisms. The first step is the production of ethyl alcohol, C
More informationDetermination of Cadmium Release from Ceramic Ware by Atomic Absorption Spectrometry
This is the example A5 of the EURACHEM / CITAC Guide "Quantifying in Analytical Measurement", Second Edition. The amount of released cadmium from ceramic ware is determined using atomic absorption spectrometry.
More informationDetermination of total hardness of water by complexonometric titration (EDTA)
Determination of total hardness of water by complexonometric titration (EDTA) SCOPE AND FIELD OF APPLICATION: The present method is used for the determination of total hardness of water in drinking water,
More informationVolumetric Analysis Acids & Bases HL
Name: Volumetric Analysis 1. Concentrations of Solutions 3. Volumetric Analysis Objectives -define solution -define concentration -define molarity -express concentration of solutions in mol/l(molarity),
More informationElectrochemistry LEC Potentiometric ph titration (phosphoric acid in a soft drink) What you need: What you can learn about
Electrochemistry LEC 06 What you can learn about Galvanic cell Types of electrodes Nernst equation Potentiometry Principle and tasks The cell voltage and the Galvani voltage of the electrodes of an galvanic
More informationChemistry 6A F2007. Dr. J.A. Mack 11/28/07. Exam 3: Friday 12/7/07 (here in lecture) Standard Solutions: What will be covered on the exam?
Chemistry 6A F2007 Dr. J.A. Mack Exam : Friday 12/7/07 (here in lecture) What will be covered on the exam? Chapter 6: 6.9-6.15 Chapter 7: All Chapter 8: All Chapter 9: 9.1-9.9 Any thing from lab as well
More informationChesapeake Campus Chemistry 111 Laboratory
Chesapeake Campus Chemistry 111 Laboratory Objectives Calculate the concentration of a secondary standard through titration with a primary standard. Titrate a sample of carbonated soda with a standard
More informationTitle Experiment 2: Acid-Base Reactions: the Identification of an Unknown Weak Acid
Title Experiment : Acid-Base Reactions: the Identification of an Unknown Weak Acid Name Manraj Gill (Lab section 1) Introduction The end goal of the set of experiments and analysis performed in this lab
More informationConcentration of Solutions
Concentration of Solutions 1 of 27 Boardworks Ltd 2016 Concentration of Solutions 2 of 27 Boardworks Ltd 2016 Measuring concentrations 3 of 27 Boardworks Ltd 2016 It is not enough to say that one concentration
More informationDetermination of equivalence point using ph titration of Potassium Hydrogen Phalate and 0.1 N Sodium Hydroxide with phenolphthalein indicator
General Chemistry II Spring Semester Bellevue College Department of Chemistry Determination of equivalence point using ph titration of Potassium Hydrogen Phalate and 0.1 N Sodium Hydroxide with phenolphthalein
More informationSTUDYING CHEMICAL REACTIONS BY TITRATION ANALYSIS
STUDYING CHEMICAL REACTIONS BY TITRATION ANALYSIS OBJECTIVES: Study the relationship of reactants & products in solution phase chemical reactions, Learn how to prepare solutions from solid and liquid stock,
More informationCaCO 3(s) + 2HCl (aq) CaCl 2(aq) + H 2 O (l) + CO 2(g) mole mass 100g 2(36.5g) 111g 18g 44g
STOICHIOMETRY II Stoichiometry in chemical equations means the quantitative relation between the amounts of reactants consumed and product formed in chemical reactions as expressed by the balanced chemical
More informationEXPERIMENT 8 A SIMPLE TITRATION
EXPERIMENT 8 A SIMPLE TITRATION Structure 8.1 Introduction Objectives 8.2 Titration Types of Indicators Types of Titrations Standard Solution 8.3 Titrimetric Experiment: Determination of the strength of
More informationChemistry 301 Test #1
Name: KEY Pledge: I have neither given nor received aid on this test Chemistry 301 Test #1 Point Total: 100 pts possible 8 pts 1. In 2-4 sentences, explain the fundamental basis of quantitative analysis
More informationSince the publication of the ISO Guide to the Expression
DE SILVA: JOURNAL OF AOAC INTERNATIONAL VOL. 86, NO. 5, 003 1077 SPECIAL GUEST EDITOR SECTION Uncertainty of Analytical Determinations GALAPPATTI M.S. DE SILVA 4, PB Alwis Perera Mawatha, Katubedda, Sri
More informationTable of Contents. Purpose... 2 Background... 2 Prelab Questions... 3 Procedure:... 3 Calculations:... 4
Table of Contents Purpose... 2 Background... 2 Prelab Questions... 3 Procedure:... 3 Calculations:... 4 CHM 212 Experiment 4 Determination of the Ka of Potassium Hydrogen Phthalate (KHP) Using a Gran Plot
More informationSpectrophotometric Determination of Ferrocyanide in Effluents
Spectrophotometric Determination of Ferrocyanide in Effluents ECN-0025-1 INTRODUCTION This method is used to determine the concentration of ferrocyanide ion in photoprocessing solution effluents. The ion
More informationChemistry 119: Experiment 6. Sampling and Analysis of a Solid Drain Cleaner
Chemistry 119: Experiment 6 Sampling and Analysis of a Solid Drain Cleaner An important factor in any analysis is the collection of the sample. How this is done depends upon the use to which the analytical
More informationEXPERIMENT. Estimate the strength of given sodium carbonate solution by titrating it against HCl solution using methyl orange as indicator.
EXPERIMENT AIM Estimate the strength of given sodium carbonate solution by titrating it against HCl solution using methyl orange as indicator. Approximately M/40 HCl solution is provided. Prepare your
More informationGETTING THE END POINT TO APPROXIMATE. Two hours
Chem 1312 Handout Experiment ONE Laboratory Time Required Special Equipment and Supplies Objective Safety First Aid GETTING THE END POINT TO APPROXIMATE THE EQUIVALENCE POINT Two hours Balance Potassium
More information# 12 ph-titration of Strong Acids with Strong Bases
# 12 ph-titration of Strong Acids with Strong Bases Purpose: A strong acid solution is titrated with a strong base solution. A titration curve is then used to determine the endpoint and find the concentration
More informationnot to be republished NCERT YOU are already aware that a substance is analysed to establish its qualitative TITRIMETRIC ANALYSIS UNIT-6
UNIT-6 TITRIMETRIC ANALYSIS YOU are already aware that a substance is analysed to establish its qualitative and quantitative chemical composition. Thus, chemical analysis can be categorised as qualitative
More information4.6 Describing Reactions in Solution
4.6 Describing Reactions in Solution The overall or formula equation for this reaction: K 2 CrO(aq) Ba(NO 3 ) 2 (aq) BaCrO 4 (s) 2KNO 3 (aq) Although the formula equation shows the reactants and products
More informationPotentiometric Determination of the pka and the Equivalent Weight of a Weak Acid
Potentiometric Determination of the pka and the Equivalent Weight of a Weak Acid Introduction In this experiment you will use a ph meter to follow changes in H + concentration during a titration. The laboratory
More informationA periodic table is attached for use with the exam. You may remove it and do not need to turn it in with the exam. Score
Gateway General Chemistry 5/6/30 Exam 3 November, 005 6:0-7:40 individual or 8:0-9:40 7:40-8:00; 9:40-0:00 team problem Name Lab GSI (Ryan or Tom) Discussion GSI (Ryan or Tom) A periodic table is attached
More informationChapter 13. Titrations in Analytical Chemistry
Chapter 13 Titrations in Analytical Chemistry Titrations in Analytical Chemistry Titration methods are based on determining the quantity of a reagent of known concentration that is required to react completely
More informationExperiment 3: Acids, Bases, and Buffers
Experiment 3: Acids, Bases, and Buffers Reading: Chemistry the Central Science, Chapter 16.1-16.7 Introduction: The reaction of an acid and a base is a neutralization reaction. The technique of accurately
More informationIntroduction to biochemical practicals. Vladimíra Kvasnicová
Introduction to biochemical practicals Vladimíra Kvasnicová arrangement of practicals laboratory safety regulations laboratory equipment dealing with automatic pipette instructions: http://vyuka.lf3.cuni.cz/
More informationExperiment 20: Analysis of Vinegar. Materials:
Experiment 20: Analysis of Vinegar Materials: graduated cylinder 6 M NaOH: Dilute Sodium Hydroxide 1000 ml Florence Flask & stopper KHC 8 H 4 O 4 : Potassium Hydrogen Phthalate (KHP) 125 ml Erlenmeyer
More informationThe topics in this unit are:
The topics in this unit are: 1 Uses of chemicals in industry 2 Acids and alkalis 1 3 Acids and alkalis 2 4 Neutralisation 5 Chemical synthesis 6 Percentage yield 7 Relative atomic mass 8 Relative formula
More informationMole Concept 5.319% = = g sample =
Mole - a counting system Avogadro s number = 6.0 10 3 Mole Concept Chemical calculation involving mass: Empirical formula: The simplest formula that shows the relative numbers of the different kinds of
More informationIf you have a Mac do whatever you have to do to play it as a slide show I don t know Macs well. Dr. Buckley
For best results please view this as a slide show. You can hit the F5 key or go to the Slide Show tab on the menu bar and click on From Beginning. Page Down and Page Up will move you through the presentation.
More informationExperiment 8 and 9 Weak Acids and Bases: Exploring the Nature of Buffers
Experiment 8 and 9 Weak Acids and Bases: Exploring the Nature of Buffers Pre-Laboratory Assignments Reading: Textbook Chapter 16 Chapter 17:1-3 This Laboratory Handout Pre-Laboratory Assignments: Complete
More informationChapter 4 Solution Stoichiometry. Dr. Sapna Gupta
Chapter 4 Solution Stoichiometry Dr. Sapna Gupta Concentrations of Solutions A solution is solute dissolved in a solvent. To quantify and know exactly how much of a solute is present in a certain amount
More informationThermodynamics and the Solubility of Sodium Tetraborate Decahydrate
Thermodynamics and the Solubility of Sodium Tetraborate Decahydrate In this experiment you, as a class, will determine the solubility of sodium tetraborate decahydrate (Na 2 B 4 O 7 10 H 2 O or Na 2 [B
More informationAcid Base Titration. Week 1. Dilute 3 M of NaOH to 600 ml.5m of NaOH. Add about 7 drops of the indicator solution (BTB).
Acid Base Titration Beginning Questions: 1) NaOH has a concentration of what? 2) HCl has a concentration of what? 3) What is the neutralization of the antacid? 4) What is the concentration of OH- in the
More informationSECTION A. a) The following Gaussian distribution plots depict the analysis of lead in milk carried out by four different laboratories.
Page Question 1 SECTION A a) The following Gaussian distribution plots depict the analysis of lead in milk carried out by four different laboratories. 7 Laboratory A True Value 7 Laboratory B True Value
More informationConcentration of Solutions
Concentration of Solutions 1 of 27 Boardworks Ltd 2016 Concentration of Solutions 2 of 27 Boardworks Ltd 2016 Measuring concentrations 3 of 27 Boardworks Ltd 2016 It is not enough to say that one concentration
More informationExperiment 7: ACID-BASE TITRATION: STANDARDIZATION OF A SOLUTION
Experiment 7: ACID-BASE TITRATION: STANDARDIZATION OF A SOLUTION Purpose: Determine molarity of a solution of unknown concentration by performing acid-base titrations Performance Goals: Apply the concepts
More informationUnit 13 Acids and Bases
Unit 13 Acids/Bases Acids can be simply defined as compounds that can produce H + ions and generally have an "H" as the first element in the formula (e.g. HCl, H2SO4, HNO3, etc.). Bases are simply defined
More informationChem 2115 Experiment #7. Volumetric Analysis & Consumer Chemistry Standardization of an unknown solution, analysis of vinegar & antacid tablets
Chem 2115 Experiment #7 Volumetric Analysis & Consumer Chemistry Standardization of an unknown solution, analysis of vinegar & antacid tablets OBJECTIVE: The goals of this experiment are to learn titration
More informationErrors. Accuracy and precision
Errors Accuracy and precision The terms accuracy and precision are commonly used to mean the same thing but there is a subtle difference in their meanings. An accurate measurement or result is defined
More informationNEUTRALIZATION TITRATION-2 TITRATION OF AN ANTACID (Exp. 4)
Objective NEUTRALIZATION TITRATION-2 TITRATION OF AN ANTACID (Exp. 4) The aim of this experiment is to carry out titration of antacid tablets and to determine acetic acid content of vinegar. a) Titration
More informationph Titration Curves You will need about 10 ml of ~6M NaOH solution and about 40 ml of each acid solution and about 1.5 grams of KHP.
ph Titration Curves In this experiment you will generate titration curves for the titration of a monoprotic strong acid, a monoprotic weak acid, and a diprotic weak acid. From the titration curves you
More informationPRACTICAL 3 ph AND BUFFERS
PRACTICAL 3 ph AND BUFFERS ph and Buffers Structure 3.1 Introduction 3.2 ph and Buffers: Basic Concept 3.2.1 ph 3.2.2 Buffers and Buffer Solutions 3.3 Methods for Determining ph Experiment 1: Measurement
More informationCHAPTER 2 MATERIALS AND GENERAL EXPERIMENTAL PROCEDURES
CHAPTER 2 MATERIALS AND GENERAL EXPERIMENTAL PROCEDURES This chapter deals with description of the materials used, experimental conditions employed, and general instrumental and electrode arrangements
More informationUnit 4a: Solution Stoichiometry Last revised: October 19, 2011 If you are not part of the solution you are the precipitate.
1 Unit 4a: Solution Stoichiometry Last revised: October 19, 2011 If you are not part of the solution you are the precipitate. You should be able to: Vocabulary of water solubility Differentiate between
More informationTitrasure standards and volumetric solutions...for guaranteed results
Titrasure standards and volumetric solutions...for guaranteed results and Titrasure standards Titration is a high-precision analytical method that requires titrants of accurately known concentration. Scharlau
More informationTitrations Worksheet and Lab
Titrations Worksheet and Lab Vocabulary 1. Buret: a piece of glassware used for dispensing accurate volumes, generally reads to two places of decimal. 2. Titrant: the substance of known concentration added
More informationSection 10.3: Acid Base Stoichiometry
Section 10.3: Acid Base Stoichiometry Tutorial 1 Questions, page 481 1. It is necessary to keep the volume of indicator used to a minimum because many acid base indicators are weak acids. Some of the base
More informationNCEA Chemistry 2.1 Quantitative Analysis AS 91161
NCEA Chemistry 2.1 Quantitative Analysis AS 91161 What is this NCEA Achievement Standard? When a student achieves a standard, they gain a number of credits. Students must achieve a certain number of credits
More informationTraceability is easy. All results are traceable. To what is the issue!
Eurachem Workshop - Validation, Alex Williams Chairman EURACHEM/CITAC Measurement Uncertainty & Traceability Working Group Traceability is easy All results are traceable To what is the issue! 1 Eurachem
More informationCHEMISTRY QUANTITATIVE AND QUALITATIVE ANALYSIS Fall 2008
CHEMISTRY 114.1 QUANTITATIVE AND QUALITATIVE ANALYSIS Fall 2008 SECTION 1. INSTRUCTOR AND COURSE INFORMATION Instructor: Mr. Xianbo Shi Office: Remsen 017 Office hours: Wednesday, 1:00-2:00 pm Telephone:
More informationLAB 8: DETERMINATION OF ACETIC ACID CONTENT IN VINEGAR
LAB 8: DETERMINATIN F AETI AID NTENT IN VINEGAR Lab format: This lab is designed for delivery using the Remote Web-based Science Laboratory (RWSL) or a lab kit. INTRDUTIN In an acid-base titration, the
More informationAnnex 2 Formaldehyde
Annex 2 Formaldehyde The 2 methods are analytical procedures for the determination of formaldehyde CH2O, PM/Ref. No 17260, and hexamethylenetetramine (HMTA) C6H12N4, PM/Ref. No 18670, in food simulants
More informationFACULTY OF SCIENCE DEPARTMENT OF CHEMICAL TECHNOLOGY NATIONAL DIPLOMA: ANALYTICAL CHEMISTRY (4 YEARS) ANALYTICAL CHEMISTRY 1AY1 (THEORY)
FACULTY OF SCIENCE DEPARTMENT OF CHEMICAL TECHNOLOGY NATIONAL DIPLOMA: ANALYTICAL CHEMISTRY (4 YEARS) MODULE CET1AY1 ANALYTICAL CHEMISTRY 1AY1 (THEORY) CAMPUS DFC NOVEMBER EXAMINATION DATE: 02/11/2015
More informationDetermination of the Equivalent Weight and Ionization Constant of a Weak Acid
Determination of the Equivalent Weight and Ionization Constant of a Weak Acid Introduction: The object of this experiment will be to determine the ionization constant, K a, and the equivalent weight of
More informationApplication Note No. 072/2012
Application Note No. 07/01 Total SO in Wine Distillation Unit K-355: Interlaboratory Test for the Determination of Total SO in Wine 1. Introduction An interlaboratory test was carried out involving four
More informationAcid-Base Titrations
Chem 1252, General Chemistry I Lab Johnson Acid-Base Titrations Introduction Titration is a convenient quantitative method for accurately determining unknown concentrations of solutions. A necessary requirement
More informationNaCl (aq) + HOH (l) + (aq) + Cl (l) Eg. HCl (aq) + NH 3(aq) In both cases the acid and base react and neutralize each other.
Acid Base Reactions An acid base reaction is called a neutralization reaction. Eg. HCl (aq) + NaOH (aq) NaCl (aq) + HOH (l) In grade 10 you learned that acid base reactions produce salt and water, however,
More informationAnalysing Acids and Bases
Week 4 Analysing Acids and Bases Acid A substance that donates a hydrogen ion (proton) A proton is donated in the acidbase reaction: HCl (aq) + H H O (aq) + Cl (aq) Strong acids completely ionise in water
More informationTitration of citric acid in juice: Technical Notes
Page 25 TECHNICAL NOTES Titration of citric acid in juice: Technical Notes Introduction This is a fairly standard titration except for the following: commercial lemon juice is used. This juice is slightly
More informationPartner: Judy 29 March Analysis of a Commercial Bleach
Partner: Judy 29 March 2012 Analysis of a Commercial Bleach Purpose: The purpose of this lab is to determine the amount of sodium hypochlorite (NaClO) in commercial bleach. This can be done by forming
More informationChapter 4: Verification of compendial methods
Chapter 4: Verification of compendial methods Introduction In order to ensure accurate and reliable test results, the quality control laboratory (QCL) needs to use analytical methods (and accompanying
More informationCHEM Practice to be done before the lab. Experiment 9 Introduction to Volumetric Techniques II. Objectives
1 CHEM 0011 Experiment 9 Introduction to Volumetric Techniques II Objectives 1. To learn the proper technique to use a burette. 2. To learn the proper technique to carry out a titration. 3. To verify the
More informationPotentiometric measurement of ph
Potentiometric measurement of ph Determination of ph can be done by simple colorimetric methods using acid-base indicators (ph test strips). Nevertheless, the precision of such methods is mostly insufficient.
More informationmohd faisol mansor/chemistry form 4/chapter 7 CHAPTER 7 ACIDS AND BASES HCl (g) H 2 O H + (aq) + Cl - (aq) NaOH(s) H 2 O Na + (aq) + OH - (aq)
CHAPTER 7 ACIDS AND BASES Arrhenius Theory An acid is a chemical compound that produces hydrogen ions, H + or hydroxonium ions H3O + when dissolve in water. A base defined as a chemical substance that
More informationLaboratory Exercises in Medical Chemistry II
Laboratory Exercises in Medical Chemistry II 1 st year, General Medicine Faculty of Medicine in Pilsen Charles University Name: Confirmation of the attendance at the labs Study group: Date: (stamp, tutor's
More informationPreLAD: b. KHP is a monoprotic acid, what are the number of moles of ionizable H + in the approximately 0.25 g of KHP?
LAD G.1 (pg! 1 of 6! ) What % of vinegar is really acetic acid? Name Per What part of the solution is really HC2H3O2 aka CH3COOH? What is the Ka of acetic acid? Introduction: The acid in vinegar is acetic
More informationShe carries out two experiments.
1 A student investigates the reaction of aqueous sodium hydroxide with two different aqueous solutions of hydrochloric acid, solution X and solution Y. She carries out two experiments. Experiment 1 Using
More informationChapter 13. Titrations in Analytical Chemistry
Chapter 13 Titrations in Analytical Chemistry Titrations are based on a reaction between the analyte ( 分析物 ) and a standard reagent known as titrant ( 滴定液 ). 1 Titration methods (titrimetric methods) are
More informationTiter determination in potentiometry
Branch General analytical chemistry Keywords Titration; potentiometric titration; titer; branch 1 Summary This Bulletin provides an overview of the potentiometric titer determination in common volumetric
More information3. Chemical industry. Because of their modular design, the instruments in the TOC-L series can be equipped for any possible measurement
3. Chemical industry The most commonly used compound in the chemical industry is water not only as a solvent in processing, but also as an energy carrier in the cooling or heating cycle. As vast amounts
More informationUnit #6, Chapter 8 Outline Acids, Bases and ph
Lesson Topics Covered 1&2 Review of Acids from Grade 11 Arrhenius acids and bases, definition chemical properties of acids & bases naming acids and bases Unit #6, Chapter 8 Outline Acids, Bases and ph
More informationchemrevise.org 22/08/2013 Titrations N Goalby Chemrevise.org Titrations
Titrations N Goalby Chemrevise.org Titrations Titrations are done often to find out the concentration of one substance by reacting it with another substance of known concentration. They are often done
More informationUncertainty of ammonium nitrogen determination in wastewater
Uncertainty of ammonium nitrogen determination in wastewater A. Drolc & M. R05 National Institute of Chemistry, LjubQana, Slovenia. Abstract The measurement uncertainty of result of ammonium nitrogen determination
More informationNational standard of People s Republic of China
National standard of People s Republic of China GB5413.24-2010 Determination of chlorine in foods for infants and young children, raw milk and dairy products Issued at 2010-03-2 Implemented at:2010-06-01
More informationEXPT. 4 DETERMINATION OF pka OF ORTHOPHOSPHORIC ACID
EXPT. DETERMINATION OF pka OF ORTHOPHOSPHORIC ACID Structure.1 Introduction Objectives.2 Principle.3 Requirements. Solutions Provided.5 Procedure.6 Observations and Calculations.7 Result.1 INTRODUCTION
More informationTotal, active and effective alkali
Accepted April 1985 White and green liquors Total, actie and effectie alkali Potentiometric titration 0 Introduction This SCAN-test Method has been deeloped for use in laboratories employing electrometric
More informationTeacher Resource and Assessment Book Exercises Unit 3 answers
Teacher Resource and Assessment Book Exercises Unit 3 answers 2. Exercise: Gravimetric analysis of chicken soup Part A 1. n(agcl) = 0.246 143.3 = 1.72 x 10 3 mole 2. Amount of NaCl in 20.00 ml aliquot
More informationChem II - Wed, 9/14/16
Chem II - Wed, 9/14/16 Do Now Drop off any study guides you want color coded Pull out stoich HW Homework See board Agenda Stoich Ch 4 Labish thing Chapter 4 Chemical Reactions & Solution Stoich Water Possesses
More informationStep 2 Calculate the concentration to the correct number of significant figures.
Q1. Calculate the molarity of these solutions: a 1.5 mol of HCl dissolved in 3.0 L of solution b 0.64 g of H 2 SO 4 dissolved in 500 ml of solution c 2.1 g of NaHCO 3 dissolved in 1.00 L of solution A1.
More informationCopper (II) Glycinate Titration
Copper (II) Glycinate Titration In this experiment you will standardize (determine the concentration of) a solution of sodium thiosulfate. You will then use that sodium thiosulfate solution to titrate
More informationName: Date: AP Chemistry. Titrations - Volumetric Analysis. Steps for Solving Titration Problems
Name: Date: AP Chemistry Titrations - Volumetric Analysis Term Volumetric analysis Burette Pipette titrate titre aliquot end point equivalence point indicator primary standard standardisation secondary
More informationDetermination of Orthophosphate Ion
Determination of Orthophosphate Ion Introduction Phosphorous, in the form of phosphate, is one of several important elements in the growth of plants. Excessive algae growth in water is stimulated by the
More informationThe method used to determine the concentration of a known substance using another, standard, solution.
Titrations What are titrations? The neutralisation reaction between an acid and a base can be very useful. If an acidic solution of known concentration (a standard solution) is added to a basic (alkaline)
More information9/24/12. Chemistry Second Edition Julia Burdge. Reactions in Aqueous Solutions
Chemistry Second Edition Julia Burdge 4 Reactions in Aqueous Solutions Copyright (c) The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 1 4 Reactions in Aqueous Solutions
More informationTHE MOLE CONCEPT III Applying Moles to Chemical Solutions ADEng. Programme Chemistry for Engineers Prepared by M. J. McNeil, MPhil.
THE MOLE CONCEPT III Applying Moles to Chemical Solutions ADEng. Programme Chemistry for Engineers Prepared by M. J. McNeil, MPhil. Department of Pure and Applied Sciences Portmore Community College Main
More informationExample: How would we prepare 500. ml of M sodium sulfate in water?
95 Example: How would we prepare 500. ml of 0.500 M sodium sulfate in water? Dissolve the appropriate amount of sodium sulfate into enough water to make 500. ml of solution. A VOLUMETRIC FLASK is a flask
More informationStoichiometry ( ) ( )
Stoichiometry Outline 1. Molar Calculations 2. Limiting Reactants 3. Empirical and Molecular Formula Calculations Review 1. Molar Calculations ( ) ( ) ( ) 6.02 x 10 23 particles (atoms or molecules) /
More informationDiquat 1,1 -ethylene-2,2 -bipyridium dibromide salt Paraquat 1,1 -dimethyl-4,4 -bipyridium dichloride salt Initial Preparation
EPA Method 549.2 Revision 1.0 Determination of Diquat and Paraquat in Drinking Water by Liquid-Solid Extraction and High Performance Liquid Chromatography with Ultraviolet Detection* UCT Products: ENVIRO-CLEAN
More information