Iodometry Titration. Redox titration of iodine and sodium thiosulphate ( Iodometry)

Size: px
Start display at page:

Download "Iodometry Titration. Redox titration of iodine and sodium thiosulphate ( Iodometry)"

Transcription

1 Iodometry Titration Redox titration of iodine and sodium thiosulphate ( Iodometry) Page: 1 Iodometry: When an oxidizing agent (e.g. KMnO 4, H 2 O 2 etc.) is added to excess iodide (I ) to produce iodine and iodine so produced is determined by titration with sodium thiosulphate ( Na 2 S 2 O 3 ) then this method is known as iodometry. In case of iodometry, reducing agent (sodium thiosulphate) is titrated directly with standard I 2 solution which is produced during a reaction (i.e. reaction of some oxidizing agents like KMnO 4, H 2 O 2 with KI). Nature of iodine: 1. Iodine is a soft oxidizing agent i.e. it get reduced to I slowly. Therefore, in presence of any (even weak) oxidizing agent it changes back into iodine from I. In other words I is a strong reducing agent, since it changes fast to I 2. I 2 + 2e 2I (Slow) It is important to note that F 2, Cl 2, Br 2 are stronger oxidizing agent than I 2. Due to its ( I 2 ) soft oxidizing nature (i.e. less tendency to get reduce or less tendency to accept electrons), mild oxidizing agents like Fe +3 (aq) can oxidize aqueous I to I 2. In other words, Fe +3 (aq) can oxidize (i.e. acts as an oxidizing agent or accepts electrons or undergoes reduction) aqueous I to I 2. Therefore, I acts as strong reducing agent. The redox reaction is shown as below. Reduction/ oxidizing agent 2Fe I 2Fe 2+ + I 2 Oxidation/reducing agent Because of this iodine/ thiosulphate titrations are used in the quantitative estimation of oxidizing agents. The oxidizing agent (like KMnO 4 /H 2 O 2 ) to be estimated is first added to excess of KI this liberates iodine. 2 I (aq) I 2 (aq) + 2e Amount of iodine liberated is then determined by titration against a solution of Na 2 S 2 O 3 of known concentration. Here oxidizing agents like KMnO 4 or H 2 O 2 Oxidises KI into I 2. I 2 (aq) + 2e 2 I (aq) 2S 2 O 3 (aq) S 4 O 2 6 (aq) +2e thiosulphate tetrathionate I 2 (aq) + 2S 2 O 3 (aq) 2 I (aq) + S 4 O 6 2 (aq)

2 Page: 2 The ionic equation of the oxidation of I to I 2 by KMnO 4 in acidic medium is as follows: MnO 4 + 8H + + 5e Mn H 2 O ] 2 2 I I 2 + 2e ] 5 10 I + 2 MnO H + 2Mn I 2 + 8H 2 O Same way, the ionic equation of the oxidation of I to I 2 by H 2 O 2 in acidic medium is as follows: 2 I + H 2 O 2 + 2H + I 2 + H 2 O 2. I 2 is not very soluble. It can evaporate from titration flask during titration. Problem with this titration is ph must be controlled. End point The end point of the titration is detected by adding the starch solution. The starch gives a blue solution as long as any iodine is present. By calculating the amount of thiosulphate used in the titration we can determine amount of iodine (I 2 ) liberated and hence the amount of oxidizing agent taken. It is important to note that KI is also an oxidizing agent since on adding KI solution to the test solution until it is in excess then following colour ppt. are obtained. (i) Yellow ppt. in case of Pb 2+ (ii) Green/ cream ppt. in case of Cu 2+ (iii) Brown ppt. in case of Fe 3+ The end point of this titration can also be determined without using starch solution. In such a case when sodium thiosulphate solution is added to I 2 solution, then brown colour of the iodine disappears at the end point.

3 Exercise: Page: 3 FA 1 is moldm- 3 potassium manganate (VII). FA 2 is an aqueous solution of sodium thiosulphate. You are required to determine the concentration of thiosulphate ions in FA 2. Procedure: Pipette out 25.0 cm 3 of FA 1 into a conical flask, add about 10 cm 3 of dilute sulphuric acid and about 10 cm 3 of aqueous potassium iodide provided. Titrate the iodine liberated with FA2. Starch indicator is not necessary. Repeat the titration as many times as you think necessary to obtain accurate results. Result: Rough Accurate Final burette reading / cm 3 Initial burette reading/ cm 3 Volume of FA 2 used Summary: cm 3 of FA 1 liberated iodine requiring cm 3 of FA2 for reduction. Questions: (a) Calculate the number of moles of mangante (VII), MnO4, ions in the 25.0 cm 3 of FA 1 pipetted out. (Turn over)

4 (b) Page: 4 Given that one mole of mangante (VII) ions liberates sufficient iodine from potassium iodide to react with five moles of thiosulphate S2O3 2 ions. Calculate the number of moles of thiosulphate ions present in the volume of FA2 that you found necessary in the titration. (c) Calculate the number of moles of thiosulphate ions in 1.00 dm 3 of FA2.

5 Questions: SOLUTION Page: 5 (a) Calculate the number of moles of mangante (VII), MnO4, ions in the 25.0 cm 3 of FA 1 pipetted out. No of moles of of mangante (VII), MnO4, ions = Molarity (M MnO4 - x V MnO4 - ) = moldm- 3 x dm 3 = mol. (b) Given that one mole of mangante (VII) ions liberates sufficient iodine from potassium iodide to react with five moles of thiosulphate S2O3 2 ions. Calculate the number of moles of thiosulphate ions present in the volume of FA2 that you found necessary in the titration. Given; One mole of iodine/ mangante (VII) ions reacts with 5 moles of of thiosulphate S2O3 2 ions. Using formula No of moles of thiosulphate S2O3 2 ions = 5 x mol. = mol (c) Calculate the number of moles of thiosulphate ions in 1.00 dm 3 of FA2. No of moles of thiosulphate ions in 1.00 dm 3 of FA 2 means it is Molarity we need to find out. Molarity = Molarity = ******

Practical Lesson No 4 TITRATIONS

Practical Lesson No 4 TITRATIONS Practical Lesson No 4 TITRATIONS Reagents: 1. NaOH standard solution 0.1 mol/l 2. H 2 SO 4 solution of unknown concentration 3. Phenolphthalein 4. Na 2 S 2 O 3 standard solution 0.1 mol/l 5. Starch solution

More information

UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS General Certifi cate of Education Advanced Subsidiary Level and Advanced Level

UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS General Certifi cate of Education Advanced Subsidiary Level and Advanced Level *2215958205* UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS General Certifi cate of Education Advanced Subsidiary Level and Advanced Level CHEMISTRY 9701/31 Advanced Practical Skills 1 October/November

More information

Chemistry 12. Determining the Amount of Vitamin C (Ascorbic Acid) in a Sample

Chemistry 12. Determining the Amount of Vitamin C (Ascorbic Acid) in a Sample Chemistry 12 Determining the Amount of Vitamin C (Ascorbic Acid) in a Sample Abstract Redox reactions are involved in a wide variety of techniques for quantitative analysis of chemical substances. The

More information

Titrations. x C A V B V A. n A n B. x C B C A C B. Acid-base titrations:

Titrations. x C A V B V A. n A n B. x C B C A C B. Acid-base titrations: Acid-base titrations: Titrations n A A + n B B products Where: n A moles of acid (A) are neutralised by n B moles of base (B). If we have a solution of known acid but of unknown concentration then we can

More information

Instructions Answer all questions in the spaces provided. Do all rough work in this book. Cross through any work you do not want to be marked.

Instructions Answer all questions in the spaces provided. Do all rough work in this book. Cross through any work you do not want to be marked. GCSE CHEMISTRY Higher Tier Chemistry 1H H Specimen 2018 Time allowed: 1 hour 45 minutes Materials For this paper you must have: a ruler a calculator the periodic table (enclosed). Instructions Answer all

More information

UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS General Certifi cate of Education Advanced Subsidiary Level and Advanced Level

UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS General Certifi cate of Education Advanced Subsidiary Level and Advanced Level UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS General Certifi cate of Education Advanced Subsidiary Level and Advanced Level *4752941019* CHEMISTRY 9701/32 Advanced Practical Skills 2 May/June 2012

More information

36. Measuring the amount of vitamin C in fruit drinks

36. Measuring the amount of vitamin C in fruit drinks 158 Microscale hemistry THE RYAL SIETY F 36. Measuring the amount of vitamin in fruit drinks Topic Level Timing Description Food, scientific methodology. Quantitative chemistry/mole calculations. Pre-16

More information

A Volumetric Analysis (Redox Titration) of Hypochlorite in Bleach

A Volumetric Analysis (Redox Titration) of Hypochlorite in Bleach CHEM 311L Quantitative Analysis Laboratory Revision 2.3 A Volumetric Analysis (Redox Titration) of Hypochlorite in Bleach In this laboratory exercise, we will determine the concentration of the active

More information

UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS General Certifi cate of Education Advanced Subsidiary Level and Advanced Level

UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS General Certifi cate of Education Advanced Subsidiary Level and Advanced Level www.xtremepapers.com UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS General Certifi cate of Education Advanced Subsidiary Level and Advanced Level *1417984110* CHEMISTRY 9701/35 Advanced Practical

More information

REDUCTION-OXIDATION TITRATIONS

REDUCTION-OXIDATION TITRATIONS REDUCTIONOXIDATION TITRATIONS A reductionoxidation reaction (Redox reaction) involves the transfer of an electron(s) from species in the reaction to another. Redox reactions allow titrations of analytes

More information

K + Cl - Metal M. Zinc 1.0 M M(NO

K + Cl - Metal M. Zinc 1.0 M M(NO Redox and Electrochemistry This section should be fresh in your minds because we just did this section in the text. Closely related to electrochemistry is redox chemistry. Count on at least one question

More information

hij Teacher Resource Bank GCE Chemistry PSA10: A2 Inorganic Chemistry Carry out a redox titration

hij Teacher Resource Bank GCE Chemistry PSA10: A2 Inorganic Chemistry Carry out a redox titration hij Teacher Resource Bank GCE Chemistry : A2 Inorganic Chemistry Copyright 2009 AQA and its licensors. All rights reserved. The Assessment and Qualifications Alliance (AQA) is a company limited by guarantee

More information

NCERT. To determine the concentration/molarity of KMnO 4

NCERT. To determine the concentration/molarity of KMnO 4 UNIT-6 TITRIMETRIC ANALYSIS (REDX REACTINS) THE oxidation and reduction reactions in aqueous solutions involve the transfer of electrons from one species to another. In the oxidation of a substance electron(s)

More information

(1) Hydrochloric acid reacts with sodium hypochlorite to form hypochlorous acid: NaOCl(aq) + HCl(aq) HOCl(aq) + NaCl(aq) hypochlorous acid

(1) Hydrochloric acid reacts with sodium hypochlorite to form hypochlorous acid: NaOCl(aq) + HCl(aq) HOCl(aq) + NaCl(aq) hypochlorous acid The Determination of Hypochlorite in Bleach Reading assignment: Chang, Chemistry 10 th edition, pages 156-159. We will study an example of a redox titration in order to determine the concentration of sodium

More information

BLEACH ANALYSIS. Suppose a bleach solution is 8.75%, by mass, sodium hypochlorite. The percent "available chlorine" could be calculated as follows:

BLEACH ANALYSIS. Suppose a bleach solution is 8.75%, by mass, sodium hypochlorite. The percent available chlorine could be calculated as follows: 1 BLEACH ANALYSIS Copyright: Department of Chemistry, University of Idaho, Moscow, ID 83844-2343. 2004. INTRODUCTION Many commercially available liquid household bleaches are dilute solutions of the oxidizing

More information

Grade 11 Chemistry Problem Solving Quiz Date: Thursday March 27, Sample Questions

Grade 11 Chemistry Problem Solving Quiz Date: Thursday March 27, Sample Questions Grade 11 Chemistry Problem Solving Quiz Date: Thursday March 27, 2014 This competition is geared towards providing a fun and educational environment to promote Chemistry and in which students can be recognized

More information

Chemistry Assessment Unit AS 1

Chemistry Assessment Unit AS 1 New Specification Centre Number 71 Candidate Number ADVANCED SUBSIDIARY (AS) General Certificate of Education January 2010 Chemistry Assessment Unit AS 1 assessing Basic Concepts in Physical and Inorganic

More information

Oxidation-Reduction Reactions

Oxidation-Reduction Reactions CHAPTER 19 REVIEW Oxidation-Reduction Reactions SECTION 1 SHORT ANSWER Answer the following questions in the space provided. 1. All the following equations involve redox reactions except (a) CaO H 2 O

More information

Leaving Cert Chemistry. Free Notes. Redox Reactions

Leaving Cert Chemistry. Free Notes. Redox Reactions Leaving Cert Chemistry Free Notes Redox Reactions Redox Reactions Oxidation in terms of electron transfer Oxidation is the loss of electrons The substance which loses electrons is said to be oxidised Oxidising

More information

1.24 Calculations and Chemical Reactions

1.24 Calculations and Chemical Reactions 1.24 Calculations and Chemical Reactions Converting quantities between different substances using a balanced equation A balanced chemical equation tells us the number of particles of a substance which

More information

Electrochemistry - ANSWERS

Electrochemistry - ANSWERS Electrochemistry - ANSWERS 1. Using a table of standard electrode potentials, predict if the following reactions will occur spontaneously as written. a) Al 3+ + Ni Ni 2+ + Al Al 3+ + 3e - Al E = -1.68

More information

Synthesis of a Coordination Compound Containing Iron and Analysis of this Compound Using Redox Methods Prelab

Synthesis of a Coordination Compound Containing Iron and Analysis of this Compound Using Redox Methods Prelab Synthesis of a Coordination Compound Containing Iron and Analysis of this Compound Using Redox Methods Prelab Name Total /10 NOTE: AT THIS POINT YOU WILL ANSWER ALL PRELAB QUESTIONS IN YOUR CARBON COPY

More information

Chemistry for the gifted and talented 61

Chemistry for the gifted and talented 61 61 Student worksheet: CDRM index 30SW Discussion of answers: CDRM index 30DA Topics Working out oxidation numbers from electronegativity values, challenging redox questions and comparing the two methods

More information

Practical Problem I (23 blue points, 23 red points) DETERMINATION OF FATTY ACIDS

Practical Problem I (23 blue points, 23 red points) DETERMINATION OF FATTY ACIDS Practical Problem I (23 blue points, 23 red points) DETERMINATION OF FATTY ACIDS The starch and phenolphtalein indicator are shared between three students. They should be returned immediately after use,

More information

Summer 2003 CHEMISTRY 115 EXAM 3(A)

Summer 2003 CHEMISTRY 115 EXAM 3(A) Summer 2003 CHEMISTRY 115 EXAM 3(A) 1. In which of the following solutions would you expect AgCl to have the lowest solubility? A. 0.02 M BaCl 2 B. pure water C. 0.02 M NaCl D. 0.02 M KCl 2. Calculate

More information

Estimation of Alcohol Content in Wine by Dichromate Oxidation followed by Redox Titration

Estimation of Alcohol Content in Wine by Dichromate Oxidation followed by Redox Titration Sirromet Wines Pty Ltd 850-938 Mount Cotton Rd Mount Cotton Queensland Australia 4165 www.sirromet.com Courtesy of Jessica Ferguson Assistant Winemaker & Chemist Downloaded from seniorchem.com/eei.html

More information

ELECTROCHEMISTRY. these are systems involving oxidation or reduction there are several types METALS IN CONTACT WITH SOLUTIONS OF THEIR IONS

ELECTROCHEMISTRY. these are systems involving oxidation or reduction there are several types METALS IN CONTACT WITH SOLUTIONS OF THEIR IONS 1 ELECTROCHEMISTRY REDOX Reduction gain of electrons Cu + 2e > Cu(s) Oxidation removal of electrons Zn(s) > Zn + 2e HALF CELLS these are systems involving oxidation or reduction there are several types

More information

Chapter 16: Tests for ions and gases

Chapter 16: Tests for ions and gases The position of hydrogen in the reactivity series Hydrogen, although not a metal, is included in the reactivity series because it, like metals, can be displaced from aqueous solution, only this time the

More information

1. Which of the following hazard warning labels should be displayed on the reagent bottle storing sodium carbonate?

1. Which of the following hazard warning labels should be displayed on the reagent bottle storing sodium carbonate? Sing Yin Secondary School Final Examination, 2014-2015 Chemistry Form Four Time allowed: 2 hours Instructions: Answer ALL questions A Periodic Table is printed on page 9 of this question paper. Atomic

More information

Solution a homogeneous mixture = A solvent + solute(s) Aqueous solution water is the solvent

Solution a homogeneous mixture = A solvent + solute(s) Aqueous solution water is the solvent Solution a homogeneous mixture = A solvent + solute(s) Aqueous solution water is the solvent Water a polar solvent: dissolves most ionic compounds as well as many molecular compounds Aqueous solution:

More information

ELECTROCHEMISTRY. these are systems involving oxidation or reduction there are several types METALS IN CONTACT WITH SOLUTIONS OF THEIR IONS

ELECTROCHEMISTRY. these are systems involving oxidation or reduction there are several types METALS IN CONTACT WITH SOLUTIONS OF THEIR IONS 1 ELECTROCHEMISTRY REDOX Reduction gain of electrons Cu 2+ + 2e > Cu (s) Oxidation removal of electrons Zn (s) > Zn 2+ + 2e HALF CELLS these are systems involving oxidation or reduction there are several

More information

The Determination of Oxalate Ion in Ferric Oxalate Trihydrate using Titrimetry

The Determination of Oxalate Ion in Ferric Oxalate Trihydrate using Titrimetry CHEM 121L General Chemistry Laboratory Revision 3.0 The Determination of Oxalate Ion in Ferric Oxalate Trihydrate using Titrimetry Learn how to perform a quantitative chemical analysis. Learn how to perform

More information

Oxidation-Reduction Reactions

Oxidation-Reduction Reactions Chapter 18 Oxidation-Reduction Reactions Note to teacher: You will notice that there are two different formats for the Sample Problems in the student textbook. Where appropriate, the Sample Problem contains

More information

Redox Titrations. -the oxidation/reduction reaction between analyte and titrant

Redox Titrations. -the oxidation/reduction reaction between analyte and titrant Redox Titrations -the oxidation/reduction reaction between analyte and titrant -titrants are commonly oxidizing agents, although reducing titrants can be used -the uivalence point is based upon: A ox +

More information

4.9 Oxidation-Reduction Reactions

4.9 Oxidation-Reduction Reactions 4.9 Oxidation-Reduction Reactions We have seen that many important substances are ionic. Sodium chloride, can be formed by the reaction of elemental sodium and chlorine: 2Na(s) Cl 2 (g) 2NaCl(s) This process

More information

. The three forms are related by the equlibria,

. The three forms are related by the equlibria, Sulfur Dioxide Sulfur dioxide in wine acts as an antioxidant and an inhibitor of microbial growth Too little sulphur dioxide and the wine may suffer bacterial attack and may suffer from oxidation, thus

More information

Solubility Rules and Net Ionic Equations

Solubility Rules and Net Ionic Equations Solubility Rules and Net Ionic Equations Why? Solubility of a salt depends upon the type of ions in the salt. Some salts are soluble in water and others are not. When two soluble salts are mixed together

More information

14-Jul-12 Chemsheets A

14-Jul-12 Chemsheets A www.chemsheets.co.uk 14-Jul-12 Chemsheets A2 009 1 BRONSTED-LOWRY ACIDS & BASES Bronsted-Lowry acid = proton donor (H + = proton) Bronsted-Lowry base = proton acceptor (H + = proton) Bronsted-Lowry acid-base

More information

Chemistry AS90171 Describe chemical reactions

Chemistry AS90171 Describe chemical reactions Chemistry AS90171 Describe chemical reactions This achievement standard involves the description of chemical reactions, including the carrying out of calculations. Achievement Merit Excellence Describe

More information

Qualitative analysis of inorganic compounds

Qualitative analysis of inorganic compounds 1 Qualitative Analysis of Inorganic Compounds Qualitative analysis of inorganic compounds The experiments are written for experienced science teaching staff to use as instructions for a supervised class

More information

Standardization of Potassium Permanganate solution with Standard Sodium Oxalate Solution.

Standardization of Potassium Permanganate solution with Standard Sodium Oxalate Solution. Experiment Number: 07 Name of the experiment: Standardization of Potassium Permanganate solution with Standard Sodium Oxalate Solution. Course: Chem-114 Name: Noor Nashid Islam Roll: 0105044 Group: A2

More information

CHEM 101 HOUR EXAM II 13-OCT-98. Directions: show all work for each question only on its corresponding numbered blue book page.

CHEM 101 HOUR EXAM II 13-OCT-98. Directions: show all work for each question only on its corresponding numbered blue book page. CHEM 101 HOUR EXAM II 13-OCT-98 Directions: show all work for each question only on its corresponding numbered blue book page. 1. Write a balanced net ionic equation for each reaction or process shown:

More information

Solution Stoichiometry Quantitative Preparation of Aqueous Solutions

Solution Stoichiometry Quantitative Preparation of Aqueous Solutions Solution Stoichiometry Quantitative Preparation of Aqueous Solutions Introduction Page 1 of 11 In this week s lab, you and your lab partner will apply your prelab calculations to the preparation of aqueous

More information

Chemistry 125/126 Hourly 1 Review Notes and Questions to check your understanding.

Chemistry 125/126 Hourly 1 Review Notes and Questions to check your understanding. Chemistry 125/126 Hourly 1 Review Notes and Questions to check your understanding. N. Kerner Experiment 3: Redox: Transferring Electrons Major Concepts A. Subtances can be ranked as oxidizing or reducing

More information

CHEM N-12 November In the electrolytic production of Al, what mass of Al can be deposited in 2.00 hours by a current of 1.8 A?

CHEM N-12 November In the electrolytic production of Al, what mass of Al can be deposited in 2.00 hours by a current of 1.8 A? CHEM161 014-N-1 November 014 In the electrolytic production of Al, what mass of Al can be deposited in.00 hours by a current of 1.8 A? The number of moles of electrons passed in.00 hours by a current of

More information

Standard answers and definitions:

Standard answers and definitions: Standard answers and definitions: 1A Rates of reaction: 1. Rate = Change in [ ] Time Is the gradient on a [ ] / t graph Units = mole dm -3 s -1 2. Initial rate Rate at t = 0 3. Rate equation = k [A] n

More information

Section B: Some Essential Background Chemistry

Section B: Some Essential Background Chemistry Section B: Some Essential Background Chemistry Soluble and insoluble salts The importance of knowing whether a salt is soluble or insoluble in water You will remember that acids react with carbonates to

More information

Chemistry Assessment Unit A2 3 Internal Assessment Practical Examination 2

Chemistry Assessment Unit A2 3 Internal Assessment Practical Examination 2 Centre Number 71 Candidate Number ADVANCED General Certificate of Education 2011 Chemistry Assessment Unit A2 3 Internal Assessment Practical Examination 2 [AC232] THURSDAY 19 MAY, MORNING TIME 2 hours

More information

21-July-13 Chemsheets GCSE 000

21-July-13 Chemsheets GCSE 000 RISK ASSESSMENTS You will need to carry out a full risk assessment for all of the practicals shown below. Information given here is just about apparatus, reagents and potential quantities aimed at groups

More information

Determination of Sodium Hypochlorite Levels in Bleach

Determination of Sodium Hypochlorite Levels in Bleach Determination of Sodium Hypochlorite Levels in Bleach Household bleach is a solution of sodium hypochlorite (NaOCl) and water. It is widely used as a disinfectant and in the bleaching of textiles and paper

More information

Buffer Solutions. Buffer Solutions

Buffer Solutions. Buffer Solutions Chapter 18 Common Ion Effect Buffers and Titration Curves A/B Titrations Salts and Solubility Product The Common Ion Effect and If a solution is made in which the same ion is produced by two different

More information

CHAPTER 4. AQUEOUS REACTION CHEMISTRY

CHAPTER 4. AQUEOUS REACTION CHEMISTRY CAPTER. AQUEOUS REACTION CEMISTRY solution - homogeneous mixture of or more substances; uniform distribution of particles and same properties throughout. A solution is composed of a solute dissolved in

More information

Chemistry Assessment Unit AS 1

Chemistry Assessment Unit AS 1 Centre Number 71 Candidate Number ADVANCED SUBSIDIARY (AS) General Certificate of Education January 2012 Chemistry Assessment Unit AS 1 assessing Basic Concepts in Physical and Inorganic Chemistry AC112

More information

SPECIMEN. All items required by teachers and candidates for this task are included in this pack.

SPECIMEN. All items required by teachers and candidates for this task are included in this pack. Advanced GCE CHEMISTRY A Unit F326: Practical Skills in Chemistry 2: Quantitative Task Specimen Task Candidates answer on the task sheet. F326 (2) All items required by teachers and candidates for this

More information

Titration Principles

Titration Principles Titration Principles General Principles Volumetric analysis refers to a collection of methods in which the volume of a solution of accurately known concentration, the standard solution, required to react

More information

Inorganic Chemistry Writing (Net Ionic) Equations for Various Reactions

Inorganic Chemistry Writing (Net Ionic) Equations for Various Reactions -1- Inorganic Chemistry Writing (Net Ionic) Equations for Various Reactions On the AP examination you will encounter a question in which you will be required to write net ionic equations for various reactions.

More information

JUNIOR COLLEGE CHEMISTRY DEPARTMENT EXPERIMENT 21 SECOND YEAR PRACTICAL. Name: Group: Date: THE CHEMISTRY OF COPPER AND IRON

JUNIOR COLLEGE CHEMISTRY DEPARTMENT EXPERIMENT 21 SECOND YEAR PRACTICAL. Name: Group: Date: THE CHEMISTRY OF COPPER AND IRON JUNIOR COLLEGE CHEMISTRY DEPARTMENT EXPERIMENT 21 SECOND YEAR PRACTICAL Name: Group: Date: COPPER THE CHEMISTRY OF COPPER AND IRON 1. To a solution of Cu 2+ ions add aqueous sodium hydroxide and heat the

More information

Acetic Acid Content of Vinegar: An Acid-Base Titration E10-1

Acetic Acid Content of Vinegar: An Acid-Base Titration E10-1 Experiment 10 Acetic Acid Content of Vinegar: An Acid-Base Titration E10-1 E10-2 The task The goal of this experiment is to determine accurately the concentration of acetic acid in vinegar via volumetric

More information

Transition elements electron configurations. Definition of a transition element. Scandium Sc [Ar] 3d 1 4s 2. Titanium Ti [Ar] 3d 2 4s 2

Transition elements electron configurations. Definition of a transition element. Scandium Sc [Ar] 3d 1 4s 2. Titanium Ti [Ar] 3d 2 4s 2 2UIT Transition elements electron configurations Key words transition element d-block electron configuration Remember that partly filled d-orbital means d 1 to d 9. Learn this definition of a transition

More information

Analysis of Vitamin C Using Iodine. Introduction

Analysis of Vitamin C Using Iodine. Introduction Analysis of Vitamin C Using Iodine Introduction Vitamin C (ascorbic acid) is oxidized to dehydroascorbic acid using a mild oxidizing agent such as iodine. The oxidation is a two- electron process, following

More information

Solubility Product Constant, K sp

Solubility Product Constant, K sp Exercise 5 Page 1 Illinois Central College CHEMISTRY 132 Laboratory Section: Name: Solubility Product Constant, K sp Equipment 2-2500 ml burette 2-250 ml beakers 0300 M NaC 2 0200 M AgNO 3 ferric alum

More information

OXIDATION-REDUCTION TITRATIONS-Permanganometry

OXIDATION-REDUCTION TITRATIONS-Permanganometry Experiment No. Date OXIDATION-REDUCTION TITRATIONS-Permanganometry INTRODUCTION Potassium permanganate, KMnO 4, is probably the most widely used of all volumetric oxidizing agents. It is a powerful oxidant

More information

I N V E S T I C E D O R O Z V O J E V Z D Ě L Á V Á N Í CHEMICAL REACTIONS

I N V E S T I C E D O R O Z V O J E V Z D Ě L Á V Á N Í CHEMICAL REACTIONS Chemical reaction = process during which original substances change to new substances, reactants turn to... The bonds of reactants... and new bonds are... The classification of reactions: 1. Classification

More information

Chemical Reactions in Water

Chemical Reactions in Water Chemical Reactions in Water Ron Robertson r2 f:\files\courses\1110-20\2010 possible slides for web\waterchemtrans.doc Acids, Bases and Salts Acids dissolve in water to give H + ions. These ions attach

More information

Chemical Reactions in Water Ron Robertson

Chemical Reactions in Water Ron Robertson Chemical Reactions in Water Ron Robertson r2 f:\files\courses\1110-20\2010 possible slides for web\waterchemtrans.doc Properties of Compounds in Water Electrolytes and nonelectrolytes Water soluble compounds

More information

Chemistry. Zumdahl, 7th edition

Chemistry. Zumdahl, 7th edition Chemistry Zumdahl, 7th edition CH4 Types of Chemical Reactions and Solution Stoichiometry Yellow lead(ii) iodide is produced when lead(ii) nitrate is mixed with potassium iodide. P.126 Contents 4.1 Water,

More information

Experiment 20. Consumer Chemistry: Vitamin C in Fruit Juices

Experiment 20. Consumer Chemistry: Vitamin C in Fruit Juices Experiment 20 Consumer Chemistry: Vitamin C in Fruit Juices The Task The goal of this experiment is to determine the concentration of vitamin C in a range of different fruit juices (fresh and preserved)

More information

6. What is the mass of a phosphorus sample which contains moles of phosphorus atoms? a g b g c g d g e. 34.

6. What is the mass of a phosphorus sample which contains moles of phosphorus atoms? a g b g c g d g e. 34. General Chemistry 1. Fall 2006. Exam 1. October 30, 2006. 64 points total. Choose the best answer for questions 1-20. You must show your work for all questions to receive credit. Be sure to include units

More information

1A Rate of reaction. AS Chemistry introduced the qualitative aspects of rates of reaction. These include:

1A Rate of reaction. AS Chemistry introduced the qualitative aspects of rates of reaction. These include: 1A Rate of reaction AS Chemistry introduced the qualitative aspects of rates of reaction. These include: Collision theory Effect of temperature Effect of concentration Effect of pressure Activation energy

More information

stoichiometry = the numerical relationships between chemical amounts in a reaction.

stoichiometry = the numerical relationships between chemical amounts in a reaction. 1 REACTIONS AND YIELD ANSWERS stoichiometry = the numerical relationships between chemical amounts in a reaction. 2C 8 H 18 (l) + 25O 2 16CO 2 (g) + 18H 2 O(g) From the equation, 16 moles of CO 2 (a greenhouse

More information

Solutions to Homework Assignment 11 CHM 152 Spring 2002

Solutions to Homework Assignment 11 CHM 152 Spring 2002 Solutions to Homework Assignment 11 CHM 152 Spring 2002 16.21 Since the acid is monoprotic, the number of moles of KOH is equal to the number of moles of acid. Moles acid = 16.4 ml 1 L 0.08133 mol = 0.00133

More information

11. What is the oxidation number (or oxidation state) of an element? 12. What happens to the oxidation number (O.N.) of an element during oxidation?

11. What is the oxidation number (or oxidation state) of an element? 12. What happens to the oxidation number (O.N.) of an element during oxidation? SUBJECT : CHEMISTRY CHAPTER-08 : REDOX REACTIONS QUESTIONS CARRYING ONE MARK: 1. Define oxidation in terms of electron transfer. 2. Give the electronic interpretation of reduction. 3. What is an oxidizing

More information

General Chemistry II Chapter 20

General Chemistry II Chapter 20 1 General Chemistry II Chapter 0 Ionic Equilibria: Principle There are many compounds that appear to be insoluble in aqueous solution (nonelectrolytes). That is, when we add a certain compound to water

More information

London Examinations IGCSE

London Examinations IGCSE Centre No. Candidate No. Surname Signature Initial(s) Paper Reference(s) 4335/2H London Examinations IGCSE Chemistry Paper 2H Higher Tier Monday 9 May 2005 Morning Time: 2 hours Examiner s use only Team

More information

Lab 4. Analysis of Vitamin C

Lab 4. Analysis of Vitamin C Lab 4. Analysis of Vitamin C Chemistry 162 Revised Winter 2011 K. Marr Prelab Assignment Before coming to lab: This exercise does not require a report in your lab notebook. Record your experimental results,

More information

Chapter 6 Oxidation-Reduction Reactions. Section 6.1 2. Which one of the statements below is true concerning an oxidation-reduction reaction?

Chapter 6 Oxidation-Reduction Reactions. Section 6.1 2. Which one of the statements below is true concerning an oxidation-reduction reaction? Chapter 6 Oxidation-Reduction Reactions 1. Oxidation is defined as a. gain of a proton b. loss of a proton c. gain of an electron! d. loss of an electron e. capture of an electron by a neutron 2. Which

More information

1332 CHAPTER 18 Sample Questions

1332 CHAPTER 18 Sample Questions 1332 CHAPTER 18 Sample Questions Couple E 0 Couple E 0 Br 2 (l) + 2e 2Br (aq) +1.06 V AuCl 4 + 3e Au + 4Cl +1.00 V Ag + + e Ag +0.80 V Hg 2+ 2 + 2e 2 Hg +0.79 V Fe 3+ (aq) + e Fe 2+ (aq) +0.77 V Cu 2+

More information

Chemistry Assessment Unit AS 1

Chemistry Assessment Unit AS 1 Centre Number 71 Candidate Number ADVANCED SUBSIDIARY (AS) General Certificate of Education January 2014 Chemistry Assessment Unit AS 1 assessing Basic Concepts in Physical and Inorganic Chemistry AC112

More information

Name: Class: Date: 2 4 (aq)

Name: Class: Date: 2 4 (aq) Name: Class: Date: Unit 4 Practice Test Multiple Choice Identify the choice that best completes the statement or answers the question. 1) The balanced molecular equation for complete neutralization of

More information

Exemplar for Internal Achievement Standard. Chemistry Level 2

Exemplar for Internal Achievement Standard. Chemistry Level 2 Exemplar for internal assessment resource Chemistry for Achievement Standard 967 Exemplar for Internal Achievement Standard Chemistry Level This exemplar supports assessment against: Achievement Standard

More information

Chapter 4 Aqueous Reactions and Solution Stoichiometry

Chapter 4 Aqueous Reactions and Solution Stoichiometry CHE Chapter Chapter Aqueous Reactions and Solution Stoichiometry. The total concentration of ions in a 0.50 M solution of HCl is. (a)..000 M (b). 0.5 M (c). 0.500 M (d). 0.065 M Explanation: Since HCl

More information

IODINE CLOCK. A Study of Reaction Rates.

IODINE CLOCK. A Study of Reaction Rates. IODINE CLOCK A Study of Reaction Rates. In this lab you will be studying the Law of Mass Action. Please review that law in your text in the chapter on Chemical Kinetics. Basically, the law states that

More information

Hong Kong Chemistry Olympiad for Secondary Schools ( ) TEST THE TEST. Hong Kong Chemistry Olympiad for Secondary Schools ( )

Hong Kong Chemistry Olympiad for Secondary Schools ( ) TEST THE TEST. Hong Kong Chemistry Olympiad for Secondary Schools ( ) Hong Kong Chemistry Olympiad for Secondary Schools (2013-2014) TEST THE TEST SHAU KEI WAN GOVERNMENT SECONDARY SCHOOL 筲箕灣官立中學 Group Members: LAM YAT LONG, ALEX 林日朗 LEUNG TSUM TONG, THOMAS 梁雋堂 WONG TING

More information

Chapter 3 Calculation with Chemical Formulas and Equations

Chapter 3 Calculation with Chemical Formulas and Equations Chapter 3 Calculation with Chemical Formulas and Equations Practical Applications of Chemistry Determining chemical formula of a substance Predicting the amount of substances consumed during a reaction

More information

Friday 13 January 2012 Afternoon

Friday 13 January 2012 Afternoon Friday 13 January 2012 Afternoon AS GCE CHEMISTRY A F321 Atoms, Bonds and Groups *F314420112* Candidates answer on the Question Paper. OCR supplied materials: Data Sheet for Chemistry A (inserted) Other

More information

Syllabus for F.4 Chemistry ( ) page 1 of 6 Sing Yin Secondary School Syllabus for Chemistry ( ) Form 4

Syllabus for F.4 Chemistry ( ) page 1 of 6 Sing Yin Secondary School Syllabus for Chemistry ( ) Form 4 Syllabus for F.4 Chemistry (2015-2016) page 1 of 6 Sing Yin Secondary School Syllabus for Chemistry (2015-2016) Form 4 AIMS AND OBJECTIVES According to the Curriculum Development Council, the broad aims

More information

2. ATOMIC, MOLECULAR AND EQUIVALENT MASSES

2. ATOMIC, MOLECULAR AND EQUIVALENT MASSES 2. ATOMIC, MOLECULAR AND EQUIVALENT MASSES INTRODUCTION: EQUIVALENT WEIGHT Since hydrogen is the lightest of all elements, it was chosen as a standard for determination of equivalent weights. On this basis,

More information

Solubility Product Constant

Solubility Product Constant Solubility Product Constant Page 1 In general, when ionic compounds dissolve in water, they go into solution as ions. When the solution becomes saturated with ions, that is, unable to hold any more, the

More information

Lab 7 Parts A & B Using Acid/Base Titrations to Measure Vinegar Concentration and the Molar Mass of an Unknown Carboxylic Acid

Lab 7 Parts A & B Using Acid/Base Titrations to Measure Vinegar Concentration and the Molar Mass of an Unknown Carboxylic Acid Lab 7 Parts A & B Using Acid/Base Titrations to Measure Vinegar oncentration and the Molar Mass of an Unknown arboxylic Acid hemistry B1A / by Daniel / Summer 2015 Purpose This is a 2 day lab. The first

More information

Oxidation-Reduction Summary and Study Assignment

Oxidation-Reduction Summary and Study Assignment Oxidation-Reduction Summary and Study Assignment The atoms in elements, ions or molecules involved in electrochemical reactions are characterized by the number of protons the atom has compared to the number

More information

Name AP CHEM / / Collected Essays Chapter 17 Answers

Name AP CHEM / / Collected Essays Chapter 17 Answers Name AP CHEM / / Collected Essays Chapter 17 Answers 1980 - #2 M(s) + Cu 2+ (aq) M 2+ (aq) + Cu(s) For the reaction above, E = 0.740 volt at 25 C. (a) Determine the standard electrode potential for the

More information

Q.1 Classify the following according to Lewis theory and Brønsted-Lowry theory.

Q.1 Classify the following according to Lewis theory and Brønsted-Lowry theory. Acid-base A4 1 Acid-base theories ACIDS & BASES - IONIC EQUILIBRIA 1. LEWIS acid electron pair acceptor H, AlCl 3 base electron pair donor NH 3, H 2 O, C 2 H 5 OH, OH e.g. H 3 N: -> BF 3 > H 3 N BF 3 see

More information

Simulation of the determination of lead azide content in waste water from explosives manufacture

Simulation of the determination of lead azide content in waste water from explosives manufacture Simulation of the determination of lead azide content in waste water from explosives manufacture Lead azide ranks in the category of intensive explosives, which may, even in an insignificant amount, initiate

More information

C u ( O H ) 2. N i ( N O 3 ) 2. N a m e C a t i o n Cation A n i o n A n i o n

C u ( O H ) 2. N i ( N O 3 ) 2. N a m e C a t i o n Cation A n i o n A n i o n Name Exam 3 Page 1 AQUEUS SLUTINS 1. (8 points) Names, formulas, and water-solubility of compounds. N a m e F o r m u l a Soluble in Water? Ammonium chloride N H 4 C l y e s C u ( H N i ( N 3 Iron(III)

More information

Types of reactions: Acid-base reactions

Types of reactions: Acid-base reactions OpenStax-CNX module: m39088 1 Types of reactions: Acid-base reactions Free High School Science Texts Project This work is produced by OpenStax-CNX and licensed under the Creative Commons Attribution License

More information

Cambridge International Examinations Cambridge International Advanced Subsidiary and Advanced Level

Cambridge International Examinations Cambridge International Advanced Subsidiary and Advanced Level Cambridge International Examinations Cambridge International Advanced Subsidiary and Advanced Level CEMISTRY 9701/21 Paper 2 Structured Questions AS Core May/June 2014 1 hour 15 minutes Candidates answer

More information

BALANCING REDOX EQUATIONS

BALANCING REDOX EQUATIONS 1 BALANCING REDOX EQUATIONS The following steps may be used to balance oxidation reduction (redox) equations by the ion electron (half reaction) method. While other methods may be successful, none is so

More information

CHEM J-2 June /01(a) What is the molarity of the solution formed when 0.50 g of aluminium fluoride is dissolved in ml of water?

CHEM J-2 June /01(a) What is the molarity of the solution formed when 0.50 g of aluminium fluoride is dissolved in ml of water? CHEM1001 2014-J-2 June 2014 22/01(a) What is the molarity of the solution formed when 0.50 g of aluminium fluoride is dissolved in 800.0 ml of water? 2 The molar mass of AlF 3 is: molar mass = (26.98 (Al)

More information

Paper 1 (7404/1): Inorganic and Physical Chemistry Mark scheme

Paper 1 (7404/1): Inorganic and Physical Chemistry Mark scheme AQA Qualifications AS Chemistry Paper (7404/): Inorganic and Physical Chemistry Mark scheme 7404 Specimen paper Version 0.6 MARK SCHEME AS Chemistry Specimen paper Section A 0. s 2 2s 2 2p 6 3s 2 3p 6

More information

1. Balance the following equation. What is the sum of the coefficients of the reactants and products?

1. Balance the following equation. What is the sum of the coefficients of the reactants and products? 1. Balance the following equation. What is the sum of the coefficients of the reactants and products? 1 Fe 2 O 3 (s) + _3 C(s) 2 Fe(s) + _3 CO(g) a) 5 b) 6 c) 7 d) 8 e) 9 2. Which of the following equations

More information