Separation by Solvent Extraction

Size: px
Start display at page:

Download "Separation by Solvent Extraction"

Transcription

1 Experiment 3 Separation by Solvent Extraction Objectives To separate a mixture consisting of a carboxylic acid and a neutral compound by using solvent extraction techniques. Introduction Frequently, organic chemists must separate an organic compound from a mixture of compounds, often derived from natural sources or products of synthetic reactions. One technique used to separate the mixture compounds is called extraction. Extraction is a process that selectively dissolves one or more of the mixture components into an appropriate solvent. The solution of these dissolved compounds is often referred to as the extract. Extraction processes include removal of soluble compounds from a solid matrix, such as in the brewing of coffee or tea, or in decaffeinating coffee with liquid carbon dioxide. In the organic chemistry laboratory, however, extraction almost always refers to the transfer of compounds from one liquid solvent to another. A compound can be separated from impurities in a solution by extracting the compound from the original (or first) solvent into a second solvent. For the process to be selective, the compound must be more soluble in the second solvent than in the first solvent, and the impurities must be insoluble in the second solvent. Additionally, the two selected solvents must be immiscible, or not soluble in one another, so that they produce two separate solvent layers. After dissolving the mixture in the first solvent, the solution is added to a second solvent. The two layers are vigorously mixed to maximize the surface area between them. This mixing facilitates the transfer of a dissolved compound from one solvent layer to another. Once the transfer process is complete, the layers are again allowed to form, as shown in Figure 1. Separation of the two layers then completes the separation of the desired compound from the impurities. 16

2 Washing is the reverse process, in which the impurities are removed to the second solvent, leaving the desired compound in the original solvent, as shown in Figure 2. Extractions using large quantities of solvents, tens or hundreds of milliliters, require a separatory funnel, as shown in Figure 3. The solvent layers are mixed by shaking the separatory funnel. Then the layers are allowed to reform. The bottom layer is drained through the stopcock; the top layer is poured from the top of the separatory funnel. Figure 3. Separatory funnel for extractions 17

3 The first requirement in the extraction process is to select two immiscible solvents. One solvent, usually aqueous (water based), should be polar in nature. The second solvent should be nonpolar and might be hydrocarbon, ether, or chlorinated solvent, such as dichloromethane. When the two immiscible solvents are placed into a container, two liquid layers are formed. The more dense solvent is always the bottom layer. It is important to identify the solvent in each layer. Hydrocarbons and ethers are less dense than water or the dilute aqueous solutions used in extractions. When one of these nonpolar solvents is used, the water layer is the bottom layer, as shown in Figure 4. However, dichloromethane is denser than water. When dichloromethane is used as the nonpolar solvent, the water layer will be the top layer, as shown in Figure 5. Although the identity of each layer can be established from the density of each solvent, their identities should be confirmed. To confirm the identities of the layers, one or two drops of water are added just below the surface of the top layer. If the drops of water fall through the top layer to the layer below, then the water layer is the bottom one. It is a good practice to save all layers in labeled containers until the experiment is complete and the desired product is isolated. Often the two solvents will not completely separate after shaking, due to the formation of an emulsion at the interface between them. An emulsion is a suspension of small droplets of one liquid in another liquid. Emulsions are generally opaque or cloudy in appearance and are often mistaken as a third layer. The small size of the droplets in an emulsion causes the separation of the two solvents to take place very slowly. Several procedures may be helpful to facilitate this separation. For example, gentle swirling of the container, addition of a few drops of saturated aqueous sodium chloride or ethanol, or addition of more solvent to dilute the solutions may help. In particularly 18

4 difficult cases, it may be necessary to filter the mixture to remove small solid particles that promote emulsion formation. A simple, but useful, guide to solubility is like dissolves like. That is, nonpolar compounds, including organic compounds, are more soluble in nonpolar solvents than in polar solvent. On the other hand, ionic and polar compounds are more soluble in polar solvents, such as water. These solubility differences can be exploited to separate nonpolar compounds from ionic or polar compounds. For example, synthetic reactions often produce ionic, inorganic salts as by products of the desired nonpolar organic product. In such cases, these salts are removed by washing the nonpolar solvent with water. The organic compound remains dissolved in the nonpolar solvent. Some organic compounds are sufficiently polar to be quite soluble in water. Extraction of such polar compounds into a nonpolar solvent is often difficult. The process can be facilitated by using the technique called salting out. Inorganic salts, such as NaCl, are dissolved in water to reduce the solubility of the organic compound in the aqueous layer. Under these conditions, the organic compound preferentially dissolves in the nonpolar layer. Extraction is a particularly effective means of separating organic compounds if one compound in the mixture can be chemically converted to an ionic form. The ionic form is soluble in an aqueous layer and can be extracted into it. Other non ionized organic compounds in the mixture will remain dissolved in the nonpolar solvent layer. Separation of the two layers results in the separation of the dissolved compounds. Ionic forms of some organic compounds can be produced by reacting them with aqueous acids or bases (Figure 6). Treatment of organic acids with bases such as sodium hydroxide (NaOH) converts these acids to water soluble anions. Reacting basic amines with dilute aqueous acid solutions such as hydrochloric acid (HCl) converts the amines to watersoluble cations. Figure 6. Conversion of organic compounds to ionic forms by reaction with base or acid 19

5 The extent to which an acid base reaction proceeds to completion depends upon the relative acidity and basicity of the reactants and products. Reactions occur so that stronger acids and bases react to produce weaker conjugate bases and acids. Recall that the pka is a measure of the acidity of an acid, as shown in Equation 1. Stronger acids have smaller pka s and their conjugate bases are inherently weaker. The position of an acid base equilibrium can then be predicted from a knowledge of the pka s of the acids involved. Stronger acids, those with a smaller pka, will react with the conjugate bases of weaker acids, those with a larger pka. An analysis of pka s indicates that aqueous NaOH can be used to extract both p toluic acid and p tert butylphenol from a nonpolar solvent, as shown in Equation 2 and 3. The stronger base, OH, removes a hydrogen ion, H +, from p toluic acid to form the salt, p toluate. The polar salt is soluble in aqueous solution. Both OH and p toluate are bases. The pka of 16 indicates that OH is a stronger base than p toluate, with a pka of 4.2. The stronger base takes H + from the weaker base. Similarly, OH is a stronger base than p tert butylphenoxide ion, with a pka of Therefore, OH takes H + from p tert butylphenol to form the water soluble p tertbutylphenoxide ion. Sodium hydrogen carbonate (NaHCO 3 ), with a pka of 6.4, is a weaker base than p tertbutylphenoxide ion, so HCO 3 will not take H + from p tert butylphenol, as shown in Equation 4. As a results p tert butylphenol is not converted to a salt in aqueous sodium hydrogen carbonate and does not become water soluble. 20

6 Although aqueous NaHCO 3 is not sufficiently basic to react with p tert butylphenol, it will react with p toluic acid to form the water soluble p toluate, as shown in Equation 5. The p toluic acid and p tert butylphenol can be recovered by adding HCl to the aqueous solutions. The p toluate and p tert butylphenoxide ions are stronger bases than is Cl, so each one takes H + from HCl. The acid forms are not water soluble and, therefore, precipitate from solution. The procedure you will use in this experiment exploits the differences in these reactions to separate salicylic acid and acetanilide from the nonpolar solvent in which they are dissolved. First, you will extract only salicylic acid into NaHCO 3 solution. Since acetanilide is neutral and so does not react with NaHCO 3, it remains dissolved in the nonpolar solvent. Then, you will add HCl to the aqueous layer to precipitate the water insoluble salicylic acid. You will isolate the precipitates from the solutions by vacuum filtration, then air dry them. To recover acetanilide, you will dry the nonpolar layer with anhydrous sodium sulfate (Na 2 SO 4 ) and evaporate the solvent in a fume hood. Finally, you will recrystallize the acetanilide. To facilitate the understanding of the experimental concept, each student should prepare a flowchart by filling in the blanks with the names or structures of the compounds prior to your lab session (next page). 21

7 Laboratory flowchart Experimental Procedure 1) Perform a leak test on your separatory funnel by adding some water, put on the cap, and close the stopcock. Shake and place the funnel on a support ring. If there is a leak, consult your instructor. 2) Obtain a 1:1 mixture of salicylic acid and acetanilide from your instructor. 3) Weigh the bag containing this mixture and transfer the mixture into the separatory funnel. Re weigh the empty bag and calculate the weight of the mixture. 4) Place 10 ml of ethyl acetate in the separatory funnel. Swirl the funnel until all of the solid compounds dissolve. 5) Add 5 ml of 10% NaHCO 3 solution. Put on the cap and shake the funnel carefully for a few seconds as demonstrated by your instructor. (*Remember to hold the separatory funnel with both hands and vent it frequently with the stopcock pointed upward and away from other people.) Settle for a few minutes and drain the aqueous layer into a beaker. 22

8 6) Extract the ethyl acetate layer with another portion of 5 ml of 10% NaHCO 3 solution. Combine the aqueous layers into the same beaker. Leave the ethyl acetate layer in the separatory funnel. 7) Chill the combined aqueous layer in an ice water bath. Acidify it by slow addition of concentrated HCl solution. Notice that foaming and precipitation occur. Continue to add HCl until no more solid is produced. 8) Filter the precipitate, transfer onto a pre weighed watch glass, and dry it on a steam bath. (Which compound should be obtained at this stage?) 9) Add 10 ml of saturated NaCl solution into the ethyl acetate layer (in the separatory funnel) to wash out polar impurities. Shake the funnel and settle for a few minutes. Drain and discard the aqueous layer. Transfer the ethyl acetate layer into an Erlenmeyer flask. 10) Dry the ethyl acetate layer with anhydrous sodium sulfate. Decant the solution into a preweighed ceramic evaporating dish. 11) Evaporate the ethyl acetate on a steam bath. (Which compound should be obtained at this stage?) 12) Calculate the recovery percentages of each compound. 13) Determine the melting points of the separated compounds. Laboratory Safety Precaution 1) Wear safety goggles and lab coat at all times while working in the laboratory. 2) Acetanilide is toxic and irritating. Concentrated hydrochloric acid is toxic and corrosive. Magnesium sulfate is irritating and hygroscopic. 3) Wash your hands thoroughly with soap or detergent before leaving the laboratory. 23

Experiment 3: Extraction: Separation of an Acidic, a Basic and a Neutral Substance

Experiment 3: Extraction: Separation of an Acidic, a Basic and a Neutral Substance 1 Experiment 3: Extraction: Separation of an Acidic, a Basic and a Neutral Substance Read pp 142-155, 161-162, Chapter 10 and pp 163-173, Chapter 11, in LTOC. View the videos: 4.2 Extraction (Macroscale);

More information

Extraction: Separation of Acidic Substances

Extraction: Separation of Acidic Substances Extraction: Separation of Acidic Substances Chemists frequently find it necessary to separate a mixture of compounds by moving a component from one solution or mixture to another. The process most often

More information

Isolation of Caffeine from Tea

Isolation of Caffeine from Tea Isolation of Caffeine from Tea Introduction A number of interesting, biologically active compounds have been isolated from plants. Isolating some of these natural products, as they are called, can require

More information

Extraction Theory. Org I Lab W. J. Kelly. Liquid-liquid extraction is a useful method to separate components (compounds) of a mixture

Extraction Theory. Org I Lab W. J. Kelly. Liquid-liquid extraction is a useful method to separate components (compounds) of a mixture Extraction Theory Org I Lab W. J. Kelly Liquid-liquid extraction is a useful method to separate components (compounds) of a mixture Let's see an example. Suppose that you have a mixture of sugar in vegetable

More information

Experiment 8 Preparation of Cyclohexanone by Hypochlorite Oxidation

Experiment 8 Preparation of Cyclohexanone by Hypochlorite Oxidation Experiment 8 Preparation of Cyclohexanone by ypochlorite xidation In this experiment we will prepare cyclohexanone from cyclohexanol using hypochlorite oxidation. We will use common household bleach that

More information

Liquid/liquid Extraction 63 LIQUID/LIQUID SEPARATION: EXTRACTION OF ACIDS OR BASES FROM NEUTRAL ORGANICS

Liquid/liquid Extraction 63 LIQUID/LIQUID SEPARATION: EXTRACTION OF ACIDS OR BASES FROM NEUTRAL ORGANICS Liquid/liquid Extraction 63 LIQUID/LIQUID SEPARATION: EXTRACTION OF ACIDS OR BASES FROM NEUTRAL ORGANICS Background Extraction is one of humankind s oldest chemical operations. The preparation of a cup

More information

ISOLATION OF CAFFEINE FROM TEA

ISOLATION OF CAFFEINE FROM TEA ISLATIN F CAFFEINE FRM TEA Introduction In this experiment, caffeine is isolated from tealeaves. The chief problem with the isolation is that caffeine does not exist alone in the tealeaves, but other natural

More information

Austin Peay State University Department of Chemistry CHEM 1111. Copper Cycle

Austin Peay State University Department of Chemistry CHEM 1111. Copper Cycle Cautions Nitric acid and sulfuric acid are toxic and oxidizers and may burn your skin. Nitrogen dioxide gas produced is hazardous if inhaled. Sodium hydroxide is toxic and corrosive and will cause burns

More information

Acid-Base Extraction.

Acid-Base Extraction. Acid-Base Extraction. Extraction involves dissolving a compound or compounds either (1) from a solid into a solvent or (2) from a solution into another solvent. A familiar example of the first case is

More information

PREPARATION AND PROPERTIES OF A SOAP

PREPARATION AND PROPERTIES OF A SOAP (adapted from Blackburn et al., Laboratory Manual to Accompany World of Chemistry, 2 nd ed., (1996) Saunders College Publishing: Fort Worth) Purpose: To prepare a sample of soap and to examine its properties.

More information

CHEM 2423 Extraction of Benzoic Acid EXPERIMENT 6 - Extraction Determination of Distribution Coefficient

CHEM 2423 Extraction of Benzoic Acid EXPERIMENT 6 - Extraction Determination of Distribution Coefficient EXPERIMENT 6 - Extraction Determination of Distribution Coefficient Purpose: a) To purify samples of organic compounds that are solids at room temperature b) To dissociate the impure sample in the minimum

More information

experiment5 Understanding and applying the concept of limiting reagents. Learning how to perform a vacuum filtration.

experiment5 Understanding and applying the concept of limiting reagents. Learning how to perform a vacuum filtration. 81 experiment5 LECTURE AND LAB SKILLS EMPHASIZED Synthesizing an organic substance. Understanding and applying the concept of limiting reagents. Determining percent yield. Learning how to perform a vacuum

More information

Non-polar hydrocarbon chain

Non-polar hydrocarbon chain THE SCIENCE OF SOAPS AND DETERGENTS 2000 by David A. Katz. All rights reserved Reproduction permitted for educational purposes as long as the original copyright is included. INTRODUCTION A soap is a salt

More information

Hands-On Labs SM-1 Lab Manual

Hands-On Labs SM-1 Lab Manual EXPERIMENT 4: Separation of a Mixture of Solids Read the entire experiment and organize time, materials, and work space before beginning. Remember to review the safety sections and wear goggles when appropriate.

More information

Recovery of Elemental Copper from Copper (II) Nitrate

Recovery of Elemental Copper from Copper (II) Nitrate Recovery of Elemental Copper from Copper (II) Nitrate Objectives: Challenge: Students should be able to - recognize evidence(s) of a chemical change - convert word equations into formula equations - perform

More information

Name Lab #3: Solubility of Organic Compounds Objectives: Introduction: soluble insoluble partially soluble miscible immiscible

Name  Lab #3: Solubility of Organic Compounds Objectives: Introduction: soluble insoluble partially soluble miscible immiscible Lab #3: Solubility of rganic Compounds bjectives: - Understanding the relative solubility of organic compounds in various solvents. - Exploration of the effect of polar groups on a nonpolar hydrocarbon

More information

Synthesis of Isopentyl Acetate

Synthesis of Isopentyl Acetate Experiment 8 Synthesis of Isopentyl Acetate Objectives To prepare isopentyl acetate from isopentyl alcohol and acetic acid by the Fischer esterification reaction. Introduction Esters are derivatives of

More information

Organic Chemistry Lab Experiment 4 Preparation and Properties of Soap

Organic Chemistry Lab Experiment 4 Preparation and Properties of Soap Organic Chemistry Lab Experiment 4 Preparation and Properties of Soap Introduction A soap is the sodium or potassium salt of a long-chain fatty acid. The fatty acid usually contains 12 to 18 carbon atoms.

More information

H 2 SO 4 heat + H 3 O +

H 2 SO 4 heat + H 3 O + Dehydration of Cyclohexanol DISCUSSION OF TE EXPERIMENT In this experiment, cyclohexanol is dehydrated by aqueous sulfuric acid to produce cyclohexene as the sole product, and carbocation rearrangement

More information

Experiment 9 - Double Displacement Reactions

Experiment 9 - Double Displacement Reactions Experiment 9 - Double Displacement Reactions A double displacement reaction involves two ionic compounds that are dissolved in water. In a double displacement reaction, it appears as though the ions are

More information

CHEM 2423 Recrystallization of Benzoic Acid EXPERIMENT 4 - Purification - Recrystallization of Benzoic acid

CHEM 2423 Recrystallization of Benzoic Acid EXPERIMENT 4 - Purification - Recrystallization of Benzoic acid EXPERIMENT 4 - Purification - Recrystallization of Benzoic acid Purpose: a) To purify samples of organic compounds that are solids at room temperature b) To dissociate the impure sample in the minimum

More information

Experiment 8 - Double Displacement Reactions

Experiment 8 - Double Displacement Reactions Experiment 8 - Double Displacement Reactions A double displacement reaction involves two ionic compounds that are dissolved in water. In a double displacement reaction, it appears as though the ions are

More information

Organic Lab 1 Make-up Experiment. Extraction of Caffeine from Beverages. Introduction

Organic Lab 1 Make-up Experiment. Extraction of Caffeine from Beverages. Introduction Organic Lab 1 Make-up Experiment Extraction of Caffeine from Beverages Introduction Few compounds consumed by Americans are surrounded by as much controversy as caffeine. One article tells us that caffeine

More information

Experiment 5 Preparation of Cyclohexene

Experiment 5 Preparation of Cyclohexene Experiment 5 Preparation of yclohexene In this experiment we will prepare cyclohexene from cyclohexanol using an acid catalyzed dehydration reaction. We will use the cyclohexanol that we purified in our

More information

PHYSICAL SEPARATION TECHNIQUES. Introduction

PHYSICAL SEPARATION TECHNIQUES. Introduction PHYSICAL SEPARATION TECHNIQUES Lab #2 Introduction When two or more substances, that do not react chemically, are blended together, the result is a mixture in which each component retains its individual

More information

Experiment 8 Synthesis of Aspirin

Experiment 8 Synthesis of Aspirin Experiment 8 Synthesis of Aspirin Aspirin is an effective analgesic (pain reliever), antipyretic (fever reducer) and anti-inflammatory agent and is one of the most widely used non-prescription drugs. The

More information

Properties of Acids and Bases

Properties of Acids and Bases Lab 22 Properties of Acids and Bases TN Standard 4.2: The student will investigate the characteristics of acids and bases. Have you ever brushed your teeth and then drank a glass of orange juice? What

More information

Acid Base Titrations

Acid Base Titrations Acid Base Titrations Introduction A common question chemists have to answer is how much of something is present in a sample or a product. If the product contains an acid or base, this question is usually

More information

Enantiomers: Synthesis, characterization, and resolution of tris(ethylenediamine)cobalt(iii) chloride Introduction:

Enantiomers: Synthesis, characterization, and resolution of tris(ethylenediamine)cobalt(iii) chloride Introduction: Enantiomers: Synthesis, characterization, and resolution of tris(ethylenediamine)cobalt(iii) chloride Introduction: The development of coordination chemistry prior to 1950 involved the synthesis and characterization

More information

Physical and Chemical Properties and Changes

Physical and Chemical Properties and Changes Physical and Chemical Properties and Changes An understanding of material things requires an understanding of the physical and chemical characteristics of matter. A few planned experiments can help you

More information

Making Biodiesel from Virgin Vegetable Oil: Teacher Manual

Making Biodiesel from Virgin Vegetable Oil: Teacher Manual Making Biodiesel from Virgin Vegetable Oil: Teacher Manual Learning Goals: Students will understand how to produce biodiesel from virgin vegetable oil. Students will understand the effect of an exothermic

More information

Page 1 of 5. Purification of Cholesterol An Oxidative Addition-Reductive Elimination Sequence

Page 1 of 5. Purification of Cholesterol An Oxidative Addition-Reductive Elimination Sequence Page 1 of 5 Purification of Cholesterol An Oxidative Addition-Reductive Elimination Sequence From your lectures sessions in CEM 2010 you have learned that elimination reactions may occur when alkyl halides

More information

CHM220 Nucleophilic Substitution Lab. Studying S N 1 and S N 2 Reactions: Nucloephilic Substitution at Saturated Carbon*

CHM220 Nucleophilic Substitution Lab. Studying S N 1 and S N 2 Reactions: Nucloephilic Substitution at Saturated Carbon* CHM220 Nucleophilic Substitution Lab Studying S N 1 and S N 2 Reactions: Nucloephilic Substitution at Saturated Carbon* Purpose: To convert a primary alcohol to an alkyl bromide using an S N 2 reaction

More information

The Reaction of Calcium Chloride with Carbonate Salts

The Reaction of Calcium Chloride with Carbonate Salts The Reaction of Calcium Chloride with Carbonate Salts PRE-LAB ASSIGNMENT: Reading: Chapter 3 & Chapter 4, sections 1-3 in Brown, LeMay, Bursten, & Murphy. 1. What product(s) might be expected to form when

More information

SYNTHESIS AND ANALYSIS OF A COORDINATION COMPOUND OF COPPER

SYNTHESIS AND ANALYSIS OF A COORDINATION COMPOUND OF COPPER Chemistry 111 Lab: Synthesis of a Copper Complex Page H-1 SYNTHESIS AND ANALYSIS OF A COORDINATION COMPOUND OF COPPER In this experiment you will synthesize a compound by adding NH 3 to a concentrated

More information

Exp#6 Extraction of Caffeine from Tea Leaves

Exp#6 Extraction of Caffeine from Tea Leaves Exp#6 Extraction of Caffeine from Tea Leaves Pre-Lab Complete items numbered 1-6 (omit number 3) as described in your lab syllabus. Make sure your data table includes the appropriate physical properties

More information

CHEMICAL REACTIONS OF COPPER AND PERCENT YIELD KEY

CHEMICAL REACTIONS OF COPPER AND PERCENT YIELD KEY CHEMICAL REACTIONS OF COPPER AND PERCENT YIELD Objective To gain familiarity with basic laboratory procedures, some chemistry of a typical transition element, and the concept of percent yield. Apparatus

More information

Experiment 7 Preparation of 1-Bromobutane

Experiment 7 Preparation of 1-Bromobutane Experiment 7 Preparation of 1-Bromobutane In this experiment you will prepare 1-bromobutane (n-butyl bromide) from n-butanol (1-butanol) using a substitution reaction under acidic conditions. This is an

More information

Chapter 6, Lesson 3: Forming a Precipitate

Chapter 6, Lesson 3: Forming a Precipitate Chapter 6, Lesson 3: Forming a Precipitate Key Concepts The ions or molecules in two solutions can react to form a solid. A solid formed from two solutions is called a precipitate. Summary Students will

More information

Neutralizing an Acid and a Base

Neutralizing an Acid and a Base Balancing Act Teacher Information Objectives In this activity, students neutralize a base with an acid. Students determine the point of neutralization of an acid mixed with a base while they: Recognize

More information

EXPERIMENT 12 A SOLUBILITY PRODUCT CONSTANT

EXPERIMENT 12 A SOLUBILITY PRODUCT CONSTANT PURPOSE: 1. To determine experimentally the molar solubility of potassium acid tartrate in water and in a solution of potassium nitrate. 2. To examine the effect of a common ion on the solubility of slightly

More information

EXPERIMENT FIVE. Preparation of Cyclohexene from Cyclohexanol: an Elimination Reaction DISCUSSION

EXPERIMENT FIVE. Preparation of Cyclohexene from Cyclohexanol: an Elimination Reaction DISCUSSION EXPERIMENT FIVE Preparation of Cyclohexene from Cyclohexanol: an Elimination Reaction DISCUSSION A secondary alcohol, such as cyclohexanol, undergoes dehydration by an E1 mechanism. The key intermediate

More information

CHEMICAL DETERMINATION OF EVERYDAY HOUSEHOLD CHEMICALS

CHEMICAL DETERMINATION OF EVERYDAY HOUSEHOLD CHEMICALS CHEMICAL DETERMINATION OF EVERYDAY HOUSEHOLD CHEMICALS Purpose: It is important for chemists to be able to determine the composition of unknown chemicals. This can often be done by way of chemical tests.

More information

DETERMINATION OF THE PERCENT COMPOSITION OF A MIXTURE

DETERMINATION OF THE PERCENT COMPOSITION OF A MIXTURE Chemistry 111 Lab: Percent Composition Page D-3 DETERMINATION OF THE PERCENT COMPOSITION OF A MIXTURE In this experiment you are to determine the composition of a mixture containing unknown proportions

More information

SOLUTIONS EXPERIMENT 13

SOLUTIONS EXPERIMENT 13 SOLUTIONS EXPERIMENT 13 OBJECTIVE The objective of this experiment is to demonstrate the concepts of concentrations of solutions and the properties of solution. Colloids will be demonstrated. EQUIPMENT

More information

Experiment 7: Titration of an Antacid

Experiment 7: Titration of an Antacid 1 Experiment 7: Titration of an Antacid Objective: In this experiment, you will standardize a solution of base using the analytical technique known as titration. Using this standardized solution, you will

More information

EXPERIMENT 3 (Organic Chemistry II) Nitration of Aromatic Compounds: Preparation of methyl-m-nitrobenzoate

EXPERIMENT 3 (Organic Chemistry II) Nitration of Aromatic Compounds: Preparation of methyl-m-nitrobenzoate EXPERIMENT 3 (Organic Chemistry II) Nitration of Aromatic Compounds: Preparation of methyl-m-nitrobenzoate Pahlavan/Cherif Purpose a) Study electrophilic aromatic substitution reaction (EAS) b) Study regioselectivity

More information

Chapter 5 Classification of Organic Compounds by Solubility

Chapter 5 Classification of Organic Compounds by Solubility Chapter 5 Classification of Organic Compounds by Solubility Deductions based upon interpretation of simple solubility tests can be extremely useful in organic structure determination. Both solubility and

More information

Experiment #8 properties of Alcohols and Phenols

Experiment #8 properties of Alcohols and Phenols Introduction Experiment #8 properties of Alcohols and Phenols As has been mentioned before, over 20 million organic compounds have been identified. If each substance had to be studied as an entity completely

More information

Lab #13: Qualitative Analysis of Cations and Anions

Lab #13: Qualitative Analysis of Cations and Anions Lab #13: Qualitative Analysis of Cations and Anions Objectives: 1. To understand the rationale and the procedure behind the separation for various cations and anions. 2. To perform qualitative analysis

More information

Determination of a Chemical Formula

Determination of a Chemical Formula 1 Determination of a Chemical Formula Introduction Molar Ratios Elements combine in fixed ratios to form compounds. For example, consider the compound TiCl 4 (titanium chloride). Each molecule of TiCl

More information

ph: Measurement and Uses

ph: Measurement and Uses ph: Measurement and Uses One of the most important properties of aqueous solutions is the concentration of hydrogen ion. The concentration of H + (or H 3 O + ) affects the solubility of inorganic and organic

More information

Expt. 4: ANALYSIS FOR SODIUM CARBONATE

Expt. 4: ANALYSIS FOR SODIUM CARBONATE Expt. 4: ANALYSIS FOR SODIUM CARBONATE Introduction In this experiment, a solution of hydrochloric acid is prepared, standardized against pure sodium carbonate, and used to determine the percentage of

More information

Saturated NaCl solution rubber tubing (2) Glass adaptor (2) thermometer adaptor heating mantle

Saturated NaCl solution rubber tubing (2) Glass adaptor (2) thermometer adaptor heating mantle EXPERIMENT 5 (Organic Chemistry II) Pahlavan/Cherif Dehydration of Alcohols - Dehydration of Cyclohexanol Purpose - The purpose of this lab is to produce cyclohexene through the acid catalyzed elimination

More information

ACID-BASE TITRATIONS: DETERMINATION OF CARBONATE BY TITRATION WITH HYDROCHLORIC ACID BACKGROUND

ACID-BASE TITRATIONS: DETERMINATION OF CARBONATE BY TITRATION WITH HYDROCHLORIC ACID BACKGROUND #3. Acid - Base Titrations 27 EXPERIMENT 3. ACID-BASE TITRATIONS: DETERMINATION OF CARBONATE BY TITRATION WITH HYDROCHLORIC ACID BACKGROUND Carbonate Equilibria In this experiment a solution of hydrochloric

More information

Physical Changes and Chemical Reactions

Physical Changes and Chemical Reactions Physical Changes and Chemical Reactions Gezahegn Chaka, Ph.D., and Sudha Madhugiri, Ph.D., Collin College Department of Chemistry Objectives Introduction To observe physical and chemical changes. To identify

More information

ph Measurement and its Applications

ph Measurement and its Applications ph Measurement and its Applications Objectives: To measure the ph of various solutions using ph indicators and meter. To determine the value of K a for an unknown acid. To perform a ph titration (OPTIONAL,

More information

Syllabus OC18 Use litmus or a universal indicator to test a variety of solutions, and classify these as acidic, basic or neutral

Syllabus OC18 Use litmus or a universal indicator to test a variety of solutions, and classify these as acidic, basic or neutral Chemistry: 9. Acids and Bases Please remember to photocopy 4 pages onto one sheet by going A3 A4 and using back to back on the photocopier Syllabus OC18 Use litmus or a universal indicator to test a variety

More information

Reminder: These notes are meant to supplement, not replace the laboratory manual. SN1 Reaction Notes

Reminder: These notes are meant to supplement, not replace the laboratory manual. SN1 Reaction Notes Reminder: These notes are meant to supplement, not replace the laboratory manual. SN1 Reaction Notes Background and Application Substitution Nucleophilic First Order (SN1) reactions are one of the most

More information

Chemistry B11 Chapter 6 Solutions and Colloids

Chemistry B11 Chapter 6 Solutions and Colloids Chemistry B11 Chapter 6 Solutions and Colloids Solutions: solutions have some properties: 1. The distribution of particles in a solution is uniform. Every part of the solution has exactly the same composition

More information

Rev 2016-09-23. Experiment 3

Rev 2016-09-23. Experiment 3 Experiment 3 PREPARATION OF A STANDARD SODIUM HYDROXIDE SOLUTION, DETERMINATION OF PURITY OF IMPURE KHP AND STANDARDIZATION OF HYDROCHLORIC ACID 2 lab periods Reading: Chapter 1 (pg 22-24), Chapter 8,

More information

Chapter 6. Solution, Acids and Bases

Chapter 6. Solution, Acids and Bases Chapter 6 Solution, Acids and Bases Mixtures Two or more substances Heterogeneous- different from place to place Types of heterogeneous mixtures Suspensions- Large particles that eventually settle out

More information

EXPERIMENT 7 Reaction Stoichiometry and Percent Yield

EXPERIMENT 7 Reaction Stoichiometry and Percent Yield EXPERIMENT 7 Reaction Stoichiometry and Percent Yield INTRODUCTION Stoichiometry calculations are about calculating the amounts of substances that react and form in a chemical reaction. The word stoichiometry

More information

Taking Apart the Pieces

Taking Apart the Pieces Lab 4 Taking Apart the Pieces How does starting your morning out right relate to relief from a headache? I t is a lazy Saturday morning and you ve just awakened to your favorite cereal Morning Trails and

More information

Standardization of NaOH

Standardization of NaOH EXPERIMENT 18 Prepared by Edward L. Brown, Lee University The student will become familiar with the techniques of titration and the use of a primary standard, Potassium Hydrogen Phthalate (KHP). Buret

More information

SODIUM CARBOXYMETHYL CELLULOSE

SODIUM CARBOXYMETHYL CELLULOSE SODIUM CARBOXYMETHYL CELLULOSE Prepared at the 28th JECFA (1984), published in FNP 31/2 (1984) and in FNP 52 (1992). Metals and arsenic specifications revised at the 55 th JECFA (2000). An ADI not specified

More information

Suggested Solutions to student questions(soap) 1. How do you explain the cleansing action of soap?

Suggested Solutions to student questions(soap) 1. How do you explain the cleansing action of soap? Suggested Solutions to student questions(soap) 1. How do you explain the cleansing action of soap? The ionic part of the soap molecule is water-soluble while the non-polar hydrocarbon part is soluble in

More information

Experiment 15 Vitamins

Experiment 15 Vitamins Experiment 15 Vitamins Part 1: Solubility of Vitamins Vitamins are organic compounds that are required as cofactors for specific enzymes. They are not synthesized in the body and therefore must be obtained

More information

EXPERIMENT 9 (Organic Chemistry II) Pahlavan - Cherif Synthesis of Aspirin - Esterification

EXPERIMENT 9 (Organic Chemistry II) Pahlavan - Cherif Synthesis of Aspirin - Esterification EXPERIMENT 9 (rganic hemistry II) Pahlavan - herif Materials Hot plate 125-mL Erlenmeyer flask Melting point capillaries Melting point apparatus Büchner funnel 400-mL beaker Stirring rod hemicals Salicylic

More information

Experiment #7: Esterification

Experiment #7: Esterification Experiment #7: Esterification Pre-lab: 1. Choose an ester to synthesize. Determine which alcohol and which carboxylic acid you will need to synthesize your ester. Write out the reaction for your specific

More information

CHEMISTRY 338 THE SYNTHESIS OF LIDOCAINE

CHEMISTRY 338 THE SYNTHESIS OF LIDOCAINE CHEMISTRY 338 THE SYTHESIS F LIDCAIE Lidocaine (1) is the common name of an important member of a category of drugs widely used as local anesthetics. Trade names for this substance include Xylocaine, Isocaine,

More information

6 Reactions in Aqueous Solutions

6 Reactions in Aqueous Solutions 6 Reactions in Aqueous Solutions Water is by far the most common medium in which chemical reactions occur naturally. It is not hard to see this: 70% of our body mass is water and about 70% of the surface

More information

The Behavior of Two Families in the Periodic Table

The Behavior of Two Families in the Periodic Table The Behavior of Two Families in the Periodic Table The Periodic Table arranges the elements in order of increasing atomic number in horizontal rows of such length that elements with similar properties

More information

SEPARATION OF A MIXTURE OF SUBSTANCES LAB

SEPARATION OF A MIXTURE OF SUBSTANCES LAB SEPARATION OF A MIXTURE OF SUBSTANCES LAB Purpose: Every chemical has a set of defined physical properties, and when combined they present a unique fingerprint for that chemical. When chemicals are present

More information

Solutions Review Questions

Solutions Review Questions Name: Thursday, March 06, 2008 Solutions Review Questions 1. Compared to pure water, an aqueous solution of calcium chloride has a 1. higher boiling point and higher freezing point 3. lower boiling point

More information

ACIDS AND BASES SAFETY PRECAUTIONS

ACIDS AND BASES SAFETY PRECAUTIONS ACIDS AND BASES Mild acids and bases are used in cooking (their reaction makes biscuits and bread rise). Acids such as those in our stomachs eat away at food or digest it. Strong acids and bases are used

More information

Petri Dish Electrolysis Electrolysis Reactions

Petri Dish Electrolysis Electrolysis Reactions elearning 2009 Introduction Petri Dish Electrolysis Electrolysis Reactions Publication No. 95008 Electrolysis is defined as the decomposition of a substance by means of an electric current. When an electric

More information

Experiment 5. Chemical Reactions A + X AX AX A + X A + BX AX + B AZ + BX AX + BZ

Experiment 5. Chemical Reactions A + X AX AX A + X A + BX AX + B AZ + BX AX + BZ Experiment 5 Chemical Reactions OBJECTIVES 1. To observe the various criteria that are used to indicate that a chemical reaction has occurred. 2. To convert word equations into balanced inorganic chemical

More information

Limiting Reagent (using an analogy and a learning cycle approach)

Limiting Reagent (using an analogy and a learning cycle approach) Limiting Reagent (using an analogy and a learning cycle approach) Welcome: This is the fourth of a four- experiment sequence, covering four important aspects of chemistry, and utilizing a learning cycle

More information

Chemical Tests for Alkanes, Alkenes, and Aromatic Compounds

Chemical Tests for Alkanes, Alkenes, and Aromatic Compounds Chemical Tests for Alkanes, Alkenes, and Aromatic Compounds Introduction There are four types of hydrocarbons: alkanes, alkenes, alkynes, and aromatic compounds, each type with different chemical properties.

More information

The Empirical Formula of a Compound

The Empirical Formula of a Compound The Empirical Formula of a Compound Lab #5 Introduction A look at the mass relationships in chemistry reveals little order or sense. The ratio of the masses of the elements in a compound, while constant,

More information

Separation and Identification of Group B Cations (Bi 3+, Fe 3+, Mn 2+, Cr 3+ and Al 3+ )

Separation and Identification of Group B Cations (Bi 3+, Fe 3+, Mn 2+, Cr 3+ and Al 3+ ) Objectives Name: Separation and Identification of Group B Cations (Bi 3+, Fe 3+, Mn 2+, Cr 3+ and Al 3+ ) To understand the chemical reactions involved in the separation and identification of the Group

More information

PURIFICATION TECHNIQUES

PURIFICATION TECHNIQUES DETERMINACIÓN DE ESTRUCTURAS ORGÁNICAS (ORGANIC SPECTROSCOPY) PURIFICATION TECHNIQUES Hermenegildo García Gómez Departamento de Química Instituto de Tecnología Química Universidad Politécnica de Valencia

More information

ionic substances (separate) based on! Liquid Mixtures miscible two liquids that and form a immiscible two liquids that form a e.g.

ionic substances (separate) based on! Liquid Mixtures miscible two liquids that and form a immiscible two liquids that form a e.g. Unit 7 Solutions, Acids & Bases Solution mixture + solvent - substance present in the amount solute - in the solvent solvent molecules solute particles ionic substances (separate) based on! Liquid Mixtures

More information

Preparation of an Alum

Preparation of an Alum Preparation of an Alum Pages 75 84 Pre-lab = pages 81 to 82, all questions No lab questions, a lab report is required by the start of the next lab What is an alum? They are white crystalline double sulfates

More information

Chemistry Ch 15 (Solutions) Study Guide Introduction

Chemistry Ch 15 (Solutions) Study Guide Introduction Chemistry Ch 15 (Solutions) Study Guide Introduction Name: Note: a word marked (?) is a vocabulary word you should know the meaning of. A homogeneous (?) mixture, or, is a mixture in which the individual

More information

GRIGNARD REACTION: PREPARATION OF TRIPHENYLMETHANOL (12/22/2009)

GRIGNARD REACTION: PREPARATION OF TRIPHENYLMETHANOL (12/22/2009) GRIGNARD REACTIN: PREPARATIN F TRIPHENYLMETHANL (12/22/2009) Grignard reagents are among the most versatile organometallic reagents, and they are the easiest organometallic reagent to prepare. Grignard

More information

Experiment 7 GRAVIMETRIC ANALYSIS OF A TWO COMPONENT MIXTURE

Experiment 7 GRAVIMETRIC ANALYSIS OF A TWO COMPONENT MIXTURE Purpose Experiment 7 GRAVIMETRIC ANALYSIS OF A TWO COMPONENT MIXTURE The purpose of the experiment is to determine the percent composition by mass of a two component mixture made up of NaHCO 3 and Na 2

More information

EXPERIMENT 11: Qualitative Analysis of Cations

EXPERIMENT 11: Qualitative Analysis of Cations EXPERIMENT 11: Qualitative Analysis of Cations Materials: Equipment: centrifuge, test tubes (6 small, 2 medium), test tube rack, stirring rods, beral pipets, hot plate, small beaker, red litmus paper.

More information

HOW TO MAKE STANDARD SOLUTIONS FOR CHEMISTRY

HOW TO MAKE STANDARD SOLUTIONS FOR CHEMISTRY HOW TO MAKE STANDARD SOLUTIONS FOR CHEMISTRY Phillip Bigelow Chemists make two common types of "standard solutions": Molar solutions Normal solutions Both of these solutions are concentrations (or strengths

More information

Stoichiometry Limiting Reagent Laboratory. Chemistry 118 Laboratory University of Massachusetts, Boston

Stoichiometry Limiting Reagent Laboratory. Chemistry 118 Laboratory University of Massachusetts, Boston Chemistry 118 Laboratory University of Massachusetts, Boston STOICHIOMETRY - LIMITING REAGENT --------------------------------------------------------------------------------------------------------------------------------------------

More information

AN EXPERIMENT IN ALCHEMY: COPPER TO SILVER TO GOLD 2005, 2000, 1996 by David A. Katz. All rights reserved

AN EXPERIMENT IN ALCHEMY: COPPER TO SILVER TO GOLD 2005, 2000, 1996 by David A. Katz. All rights reserved AN EXPERIMENT IN ALCHEMY: COPPER TO SILVER TO GOLD 2005, 2000, 1996 by David A. Katz. All rights reserved INTRODUCTION One of the goals of the ancient alchemists was to convert base metals into gold. Although

More information

Molarity of Ions in Solution

Molarity of Ions in Solution APPENDIX A Molarity of Ions in Solution ften it is necessary to calculate not only the concentration (in molarity) of a compound in aqueous solution but also the concentration of each ion in aqueous solution.

More information

MASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of Chemistry 5.310 Laboratory Chemistry THE POTENTIOMETRIC TITRATION OF AN ACID MIXTURE 1

MASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of Chemistry 5.310 Laboratory Chemistry THE POTENTIOMETRIC TITRATION OF AN ACID MIXTURE 1 MASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of Chemistry 5.310 Laboratory Chemistry EXPERIMENT #5 THE POTENTIOMETRIC TITRATION OF AN ACID MIXTURE 1 I. PURPOSE OF THE EXPERIMENT In this experiment

More information

Teacher Demo: Turning Water into Wine into Milk into Beer

Teacher Demo: Turning Water into Wine into Milk into Beer SNC2D/2P Chemical Reactions/Chemical Reactions and their Practical Applications Teacher Demo: Turning Water into Wine into Milk into Beer Topics evidence of chemical change types of chemical reactions

More information

Properties of Alcohols and Phenols Experiment #3

Properties of Alcohols and Phenols Experiment #3 Properties of Alcohols and Phenols Experiment #3 Objectives: To observe the solubility of alcohols relative to their chemical structure, to perform chemical tests to distinguish primary, secondary and

More information

Juice Titration. Background. Acid/Base Titration

Juice Titration. Background. Acid/Base Titration Juice Titration Background Acids in Juice Juice contains both citric and ascorbic acids. Citric acid is used as a natural preservative and provides a sour taste. Ascorbic acid is a water-soluble vitamin

More information

Experiment #10: Liquids, Liquid Mixtures and Solutions

Experiment #10: Liquids, Liquid Mixtures and Solutions Experiment #10: Liquids, Liquid Mixtures and Solutions Objectives: This experiment is a broad survey of the physical properties of liquids. We will investigate solvent/solute mixtures. We will study and

More information

Synthesis of Aspirin and Oil of Wintergreen

Synthesis of Aspirin and Oil of Wintergreen Austin Peay State University Department of hemistry hem 1121 autions Purpose Introduction Acetic Anhydride corrosive and a lachrymator all transfers should be done in the vented fume hood Methanol, Ethanol

More information

DYES AND DYEING 2003 by David A. Katz. All rights reserved. Permission for classroom use provided original copyright is included.

DYES AND DYEING 2003 by David A. Katz. All rights reserved. Permission for classroom use provided original copyright is included. DYES AND DYEING 2003 by David A. Katz. All rights reserved. Permission for classroom use provided original copyright is included. Dyeing of textiles has been practiced for thousands of years with the first

More information