Melting Point, Boiling Point, and Index of Refraction

Size: px
Start display at page:

Download "Melting Point, Boiling Point, and Index of Refraction"

Transcription

1 Melting Point, Boiling Point, and Index of Refraction Melting points, boiling points, and index of refractions are easily measured physical properties of organic compounds useful in product characterization and purity determination. A. Melting Points Pure, crystalline solids have a characteristic melting point, which is expressed as the temperature range over which the solid melts to become a liquid. The transition between the solid and the liquid is so sharp for small samples of a pure substance that melting points can be measured to ±0.1 o C. Typically it is no more than ±1 o C. Melting points of pure compounds are recorded in handbooks, such as the Handbook of Chemistry and Physics (CRC) or the Merck Index. Alternatively, you can find this information on the Internet, for example at Measurements of the melting point of a solid can also provide information about the purity of the substance. Pure crystalline solids have a sharp melting point. They melt in a very narrow range (melting range) of temperatures, whereas mixtures melt with a broad temperature range. Mixtures also tend to melt at temperatures below the melting points of the pure solids. Many solid substances prepared in the organic laboratory are initially impure. These impurities affect the melting point of a substance. In a sample that contains a mixture of two compounds, each component usually depresses the melting point of the other, giving an observed melting point range that is lower and broader than the melting point of either component. A melting point composition diagram for two hypothetical solids, A and B, is shown below, as a graph of temperature versus composition. The eutectic point is the lowest temperature of the mixture and is determined by the equilibrium composition at which A and B melt in constant ratio. A sample whose composition is exactly that of the eutectic point will exhibit a sharp melting point at the eutectic temperature. This means a eutectic mixture can be mistaken for a pure compound since both have a sharp melting point. Because it is difficult to heat solids to temperatures above their melting points, and because pure solids tend to melt over a very small temperature range, melting points are often used to help identify compounds.

2 We will use the Mel-Temp apparatus for measuring the melting point in our lab. The Mel-Temp apparatus uses closed-end capillary tubes. The sample is placed into a predesigned slot and its melting behavior observed through a magnifying glass. Keep in mind that we have 5 Mel-Temps for the labs. Schedule your lab experiment to minimize waiting time. I. Melting points are best determined using a finely divided powder. Grind the sample using a mortar and pestle to ensure homogeneity. Fill a capillary tube to a height of no more than 2-3 mm with the packed urea. The sample can be packed tightly by dropping the capillary tube through glass tubing on a table top or the floor. Put the tube into the Mel-temp apparatus closed end down. Make sure that you can see the sample through the magnifying glass. Set the voltage to zero and turn on the Mel-temp. Turn the voltage to 45 and observe both the sample and temperature reading as you heat. (Never set the voltage at more than 70). Note (a) the temperature at which the column of urea first collapses or shows some liquid and (b) the temperature at which the sample is completely liquid. This is the melting range, which we call a melting point. Always report a melting range. The melting point is not accurate if the thermometer and the sample are not at the same temperature. For accuracy the sample should be heated through the melting range at a rate of 1 o C or less per minute. Turn off the apparatus and let it cool. If you did not get a good result for the melting point of urea, prepare a sample in a new capillary, and repeat the measurement. Capillaries cannot be reused. Put used capillaries in the glass waste container. II. Prepare a melting point diagram for a mixture of two compounds. We will use urea and cinnamic acid. Work in groups of two for this part. Record the melting point ranges of urea (from part I), pure cinnamic acid, a 1:1 urea:cinnamic acid mixture, a 4:1 urea:cinnamic acid mixture, and a 1:4 urea:cinnamic acid mixture Plot your data in a melting point composition diagram similar to the above diagram. Make an accurate diagram using graph paper and record melting point ranges.

3 III. You will be given a solid unknown. Your unknown is one of the following compounds: salicylic acid, benzoic acid, succinic acid, acetanilide, benzophenone, or napthalene. Samples of all of these compounds are available in the lab. In the procedure part of your Prelab explain how you plan to identify your unknown. Data and Observations Record the melting ranges obtained directly into your lab notebook. List any important observations you make while performing the experiment. For example, describe the appearance of a compound when it melts and any other visible changes occurring prior to, or during, the melting process, i.e. water vapor, gas bubbles, color changes, clarity of the liquid melt. Analysis Compare the literature melting points of all substances you have used and compare to the values you have determined experimentally. Comment on any discrepancies. Compare the melting point ranges of your pure urea and cinnamic acid with the mixture. Is it possible to estimate the eutectic point from your graph? Questions 1. How fast do you heat the sample in the Mel-temp when determining a melting point? 2. If you heat too fast, will your observed melting point be higher or lower than the true value? Explain. 3. What is meant by the term melting range? What happens at this range? 4. Why should you always use a new capillary tube with a sample of your compound when doing a second melting point determination? B. Boiling Points The boiling points of pure organic liquids are, like the melting points, characteristic physical properties. The process of determining the boiling point is more complex than that for the melting point. It requires more material, and because it is less affected by impurities, it is not a good indication of purity. Like the melting point, the boiling point of a liquid is affected by the forces that attract one moleucle to another-ionic attraction, dipole-dipole interaction, hydrogen bonding, and van der Waals forces. A very clean liquid in a very clean vessel will superheat and not boil when subjected to a temperature above its boiling point. If boiling does occur under these conditions, it occurs with explosive violence. To avoid this problem boiling stones or a boiling stick is always added to liquids before heating them to boiling. 1. Practice your boiling point determination techniques, by placing about 0.3 ml of one of the liquids provided and a boiling stone in a reaction tube. Fit a distillation head (connecting adapter) on top of the reaction tube to ensure that the system is open to the atmosphere. REMEMBER TO NEVER HEAT A CLOSED SYSTEM! Using a thermometer adapter clamp a thermometer so that the bulb is just above the liquid, and then heat the liquid with a sand bath or a water bath (depending on the boiling point of your liquid, above 100 o C a sand bath, below 100 o C a water bath). Heating is regulated so that the boiling liquid refluxes (condenses the drips down) about 3 cm up the thermometer bulb in order to heat the mercury thoroughly. The boiling point is the highest temperature recorded by the thermometer and maintained over about a 1-min

4 time interval. True boiling is indicated by drops dripping from the thermometer and a constant temperature recorded on the thermometer. If the temperature is not constant, then you are probably not observing true boiling. 2. You will be given a liquid unknown. Your unknown is one of the following liquids: toluene, ethanol, cyclohexane, 1-butanol, or distilled water. All of the liquids will be available in the lab. In the procedure part of your lab, explain how you plan to identify your unknown using the boiling point and refractive index. Observation Record all your data directly in your lab notebook and compare experimental results with literature values. Comment on any discrepancies. Analysis Explain how you identified your liquid unknown using the boiling point and index of refraction. Comment on the technique of boiling point determination and refluxing and the use of the refractometer. Questions 1. What are the consequences of heating a closed system? 2. Which would you expect to have a higher boiling point, ethanol or dimethyl ether? Explain. C. Refractive Indices The refractive index is a physical constant that, like the boiling point, can be used to characterize liquids. It is the ratio of the velocity of light in air to the velocity of light in the liquid. The angle of refraction is a function of temperature and the wavelength of light. Because the velocity of light in air is always greater than that through a liquid, the refractive index is a number greater than 1; for example, hexane n 20 D The superscript 20 indicates that the measurement was made at 20 o C, and the subscript D refers to the yellow D-line of a sodium vapor lamp, light with a wavelength of 589 nm. The measurement is made with a refractometer using a few drops of liquid. Compensation is made within the instrument for the fact that white light and not sodium vapor light is used, but a temperature correction must be applied to the observed reading by adding for each degree above 20 o C. n 20 D = n t D (t 20 o C)

5 The refractive index can be determined to 1 part in 10,000, but because the value is quite sensitive to impurities, there is not always very good agreement with the literature with regard to the last figure. To master the technique of using the refractometer, measure the refractive indices of several known, pure liquids before measuring an unknown. For more information on the Abbe-3L refractometer (the instrument we have in the lab) and some video clips demonstrating its us, please go to Two or three drops of the sample are placed on the open prism using a polyethylene pipette (to avoid scratching the prism face). The prism is closed, and the light is turned on and positioned for maximum brightness as seen through the eyepiece. If the refractometer is set to a nearly correct value, then a partially gray image will be seen. Turn the knob so that the line separating the dark and light areas is at the crosshairs. Sometimes the line separating the dark and light areas is fuzzy and colored. Turn the chromatic adjustment until the demarcation line is sharp and colorless. Then read the refractive index by pressing the button down to light up the scale in the field of vision. Read the temperature on the thermometer attached to the refractometer, and make the appropriate temperature correction to the observed index of refraction. Write up a procedure for using the value of the index of refraction in addition to the boiling point determination, to identify your unknown.

EXPERIMENT 1 (Organic Chemistry I)

EXPERIMENT 1 (Organic Chemistry I) EXPERIMENT 1 (Organic Chemistry I) Melting Point Determination Purpose a) Determine the purity of a substance using melting point as physical property b) Identify an unknown compound using its melting

More information

Determination of Melting Points

Determination of Melting Points Determination of Melting Points This experiment consists of three parts. In the first part, you will determine the melting point range of three known compounds. This part is mostly for practice, to make

More information

ANALYSIS OF ASPIRIN INFRARED (IR) SPECTROSCOPY AND MELTING POINT DETERMINATION

ANALYSIS OF ASPIRIN INFRARED (IR) SPECTROSCOPY AND MELTING POINT DETERMINATION Chem 306 Section (Circle) M Tu W Th Name Partners Date ANALYSIS OF ASPIRIN INFRARED (IR) SPECTROSCOPY AND MELTING POINT DETERMINATION Materials: prepared acetylsalicylic acid (aspirin), stockroom samples

More information

EXPERIMENT 2: Recrystallization and Melting Point

EXPERIMENT 2: Recrystallization and Melting Point Recrystallization (or Crystallization) is a technique used to purify solids. This procedure relies on the fact that solubility increases as temperature increases (you can dissolve more sugar in hot water

More information

Observe and measure the effect of a solute on the freezing point of a solvent. Determine the molar mass of a nonvolatile, nonelectrolyte solute

Observe and measure the effect of a solute on the freezing point of a solvent. Determine the molar mass of a nonvolatile, nonelectrolyte solute Chapter 10 Experiment: Molar Mass of a Solid OBJECTIVES: Observe and measure the effect of a solute on the freezing point of a solvent. Determine the molar mass of a nonvolatile, nonelectrolyte solute

More information

Refractometry. Introduction

Refractometry. Introduction Refractometry Introduction A refractometer measures the extent to which light is bent (i.e. refracted) when it moves from air into a sample and is typically used to determine the index of refraction (aka

More information

Physical Properties of a Pure Substance, Water

Physical Properties of a Pure Substance, Water Physical Properties of a Pure Substance, Water The chemical and physical properties of a substance characterize it as a unique substance, and the determination of these properties can often allow one to

More information

In this experiment, we will use three properties to identify a liquid substance: solubility, density and boiling point..

In this experiment, we will use three properties to identify a liquid substance: solubility, density and boiling point.. Identification of a Substance by Physical Properties 2009 by David A. Katz. All rights reserved. Permission for academic use provided the original copyright is included Every substance has a unique set

More information

Recrystallization and Melting Points. Benzoic Acid was recrystallized with a 41% recovery using 95% ethanol and water as

Recrystallization and Melting Points. Benzoic Acid was recrystallized with a 41% recovery using 95% ethanol and water as Lab #1 (Section 102) September 17, 2002 Recrystallization and Melting Points Abstract: Benzoic Acid was recrystallized with a 41% recovery using 95% ethanol and water as the mixed-solvent. Benzoic acid

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

Objectives: 1. To learn the theory and procedure of melting points.

Objectives: 1. To learn the theory and procedure of melting points. Melting Points Objectives: 1. To learn the theory and procedure of melting points. Discussion: Crystalline solids exist in an ordered network of atoms, ions, or molecules, depending on the element or compound.

More information

Experiment 1: Thin Layer Chromatography

Experiment 1: Thin Layer Chromatography Experiment 1: Thin Layer Part A: understanding R f Part B: R f & solvent polarity Part C: R f & compound functionality Part D: identification of commercial food dye components Reading: MHS Ch. 17 pgs 219-235

More information

EXPERIMENT 7 DISTILLATION PRELAB ASSIGNMENT

EXPERIMENT 7 DISTILLATION PRELAB ASSIGNMENT EXPERIMENT 7 DISTILLATION PRELAB ASSIGNMENT 1. Prepare a Table of Physical Constants for this experiment, for the compounds, ethyl acetate and 1-butanol. Include boiling point and refractive index. 2.

More information

Molar Mass by Freezing Point Depression AP Chemistry Laboratory #4

Molar Mass by Freezing Point Depression AP Chemistry Laboratory #4 Catalog No. AP6356 Publication No. 6356A Molar Mass by Freezing Point Depression AP Chemistry Laboratory #4 Introduction A procedure for determining the molar mass of a substance is very useful to chemists.

More information

Fractional Distillation notes

Fractional Distillation notes Reminder: These notes are meant to supplement, not replace, the textbook and laboratory manual. Fractional Distillation notes History and Application: Fractional distillation is one of the most widely

More information

Distillation Experiment

Distillation Experiment Distillation Experiment CHM226 Background The distillation process is a very important technique used to separate compounds based on their boiling points. A substance will boil only when the vapor pressure

More information

Introducing Measurements in the Laboratory

Introducing Measurements in the Laboratory Introducing Measurements in the Laboratory Objectives The objectives of this laboratory are: a) To use a metric ruler to measure the dimensions of regular geometric shapes, and to use these measurements

More information

Organic Chemistry Laboratory 2230 Final Exam Study Guide

Organic Chemistry Laboratory 2230 Final Exam Study Guide Organic Chemistry Laboratory 2230 Final Exam Study Guide Many students do not adequately prepare for the final exam in 2230L.The average grade is typically in the mid to upper 60 s. Each semester, some

More information

1. The Solubility of a Salt

1. The Solubility of a Salt 1. The Solubility of a Salt Objective In this experiment, you will determine the solubility of a given salt at various temperatures. Also you will prepare the solubility curve for your salt. Introduction

More information

Melting Range. Melting Range 3

Melting Range. Melting Range 3 Melting Range 3 Melting Range Background Information The melting range of a pure solid organic is the temperature range at which the solid is in equilibrium with its liquid. As heat is added to a solid,

More information

Experiment 4 Fractional Distillation of Unknown Mixture

Experiment 4 Fractional Distillation of Unknown Mixture Experiment 4 Fractional Distillation of Unknown Mixture In this experiment you are not going to synthesize a new compound but you are going to use the technique of fractional distillation to separate an

More information

Melting Range 1 Experiment 2

Melting Range 1 Experiment 2 Melting Range 1 Experiment 2 Background Information The melting range of a pure organic solid is the temperature range at which the solid is in equilibrium with its liquid. As heat is added to a solid,

More information

Consider next the behavior of a mixture of two liquid compounds. The example shown below is for a 1:1 mixture of cyclohexane (C) and toluene (T).

Consider next the behavior of a mixture of two liquid compounds. The example shown below is for a 1:1 mixture of cyclohexane (C) and toluene (T). Distillation Distillation is a commonly used method for purifying liquids and separating mixtures of liquids into their individual components. Familiar examples include the distillation of crude fermentation

More information

Determination of the Molecular Weight of a Volatile Liquid

Determination of the Molecular Weight of a Volatile Liquid CHEM 121L General Chemistry Laboratory Revision 1.2 Determination of the Molecular Weight of a Volatile Liquid Learn about the Gas Laws. Learn about the Dumas Method of Molecular Weight determinations.

More information

Chemistry 112 Laboratory Experiment 6: The Reaction of Aluminum and Zinc with Hydrochloric Acid

Chemistry 112 Laboratory Experiment 6: The Reaction of Aluminum and Zinc with Hydrochloric Acid Chemistry 112 Laboratory Experiment 6: The Reaction of Aluminum and Zinc with Hydrochloric Acid Introduction Many metals react with acids to form hydrogen gas. In this experiment, you will use the reactions

More information

Experiment 2 Microscale Density and Refractometry

Experiment 2 Microscale Density and Refractometry Experiment 2 Microscale Density and Refractometry OUTCOMES After completing this experiment, the student should be able to: make a micropycnometer from a Pasteur pipet. calculate the density of a liquid

More information

Pre-Lab Notebook Content: Your notebook should include the title, date, purpose, procedure; data tables.

Pre-Lab Notebook Content: Your notebook should include the title, date, purpose, procedure; data tables. Determination of Molar Mass by Freezing Point Depression M. Burkart & M. Kim Experimental Notes: Students work in pairs. Safety: Goggles and closed shoes must be worn. Dispose of all chemical in the plastic

More information

1. The Determination of Boiling Point

1. The Determination of Boiling Point 1. The Determination of Boiling Point Objective In this experiment, you will first check your thermometer for errors by determining the temperature of two stable equilibrium systems. You will then use

More information

ESSAY. Write your answer in the space provided or on a separate sheet of paper.

ESSAY. Write your answer in the space provided or on a separate sheet of paper. Test 1 General Chemistry CH116 Summer, 2012 University of Massachusetts, Boston Name ESSAY. Write your answer in the space provided or on a separate sheet of paper. 1) Sodium hydride reacts with excess

More information

5. Which temperature is equal to +20 K? 1) 253ºC 2) 293ºC 3) 253 C 4) 293 C

5. Which temperature is equal to +20 K? 1) 253ºC 2) 293ºC 3) 253 C 4) 293 C 1. The average kinetic energy of water molecules increases when 1) H 2 O(s) changes to H 2 O( ) at 0ºC 3) H 2 O( ) at 10ºC changes to H 2 O( ) at 20ºC 2) H 2 O( ) changes to H 2 O(s) at 0ºC 4) H 2 O( )

More information

Recrystallization. Good. Bad. solubility ---> Bad. temperature --->

Recrystallization. Good. Bad. solubility ---> Bad. temperature ---> Recrystallization. Recrystallization is the primary method for purifying solid organic compounds. Compounds obtained from natural sources or from reaction mixtures almost always contain impurities. The

More information

Determination of Molar Mass by Freezing-Point Depression

Determination of Molar Mass by Freezing-Point Depression DETERMINATION OF MOLAR MASS BY FREEZING-POINT DEPRESSION 141 Determination of Molar Mass by Freezing-Point Depression OBJECTIVES: Gain familiarity with colligative properties of nonelectrolyte solutions

More information

Colligative Properties: Freezing Point Depression and Molecular Weight

Colligative Properties: Freezing Point Depression and Molecular Weight Purpose: Colligative Properties: Freezing Point Depression and Molecular Weight The first purpose of this lab is to experimentally determine the van't Hoff (i) factor for two different substances, sucrose

More information

Green Principles Atom Economy Solventless Reactions Catalysis

Green Principles Atom Economy Solventless Reactions Catalysis Lab 5: The Aldol Reaction Solventless vs Traditional Reactions: (Melting Point Study & Recrystallization) (adapted from Doxsee, K.M. and Hutchison, J.E., Green Organic Chemistry and John Thompson; Lane

More information

Lab # 4: Separation of a Mixture Lab Objective Introduction

Lab # 4: Separation of a Mixture Lab Objective Introduction Name: Lab Partner(s): Date Completed: Lab # 4: Separation of a Mixture Lab Accelerated Chemistry 1 Objective You will be given a mixture containing sodium chloride (NaCl, table salt), benzoic acid (C 7

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

Experiment 2: Fractional Distillation of a Mixture of Two Unknowns

Experiment 2: Fractional Distillation of a Mixture of Two Unknowns Experiment 2: Fractional Distillation of a Mixture of Two Unknowns Background: Boiling is a process familiar to anyone who has cooked pasta or brewed tea. As heat is applied to a pan of water, the temperature

More information

Chemistry 212 VAPOR PRESSURE OF WATER LEARNING OBJECTIVES

Chemistry 212 VAPOR PRESSURE OF WATER LEARNING OBJECTIVES Chemistry 212 VAPOR PRESSURE OF WATER LEARNING OBJECTIVES The learning objectives of this experiment are to explore the relationship between the temperature and vapor pressure of water. determine the molar

More information

Name Date Class MATTER AND CHANGE. SECTION 2.1 PROPERTIES OF MATTER (pages 39 42)

Name Date Class MATTER AND CHANGE. SECTION 2.1 PROPERTIES OF MATTER (pages 39 42) Name Date Class 2 MATTER AND CHANGE SECTION 2.1 PROPERTIES OF MATTER (pages 39 42) This section helps you distinguish extensive from intensive properties and identify substances by their properties. It

More information

Experiment 5: Molecular Weight Determination From Freezing Point Depression

Experiment 5: Molecular Weight Determination From Freezing Point Depression Experiment 5: Molecular Weight Determination From Freezing Point Depression PURPOSE To become familiar with colligative properties and to use them to determine the molar mass of a substance APPARATUS AND

More information

Phase Diagram of tert-butyl Alcohol

Phase Diagram of tert-butyl Alcohol Phase Diagram of tert-butyl Alcohol Bill Ponder Department of Chemistry Collin College Phase diagrams are plots illustrating the relationship of temperature and pressure relative to the phase (or state

More information

Properties of Matter and Density

Properties of Matter and Density Cautions Flames will be used and some of the chemicals will have odors and may stain your hands or clothes if you come into direct contact with them. Purpose In this experiment you will characterize common

More information

Experiment 5: Column Chromatography

Experiment 5: Column Chromatography Experiment 5: Column Chromatography Separation of Ferrocene & Acetylferrocene by Column Chromatography Reading: Mohrig, Hammond & Schatz Ch. 18 pgs 235-253 watch the technique video on the course website!

More information

15. Liquid-in-Glass Thermometry

15. Liquid-in-Glass Thermometry 123 15. Liquid-in-Glass Thermometry Even though the liquid-in-glass thermometer is used much less frequently today than formerly, it is still a very commonly used device. Although it is normally an instrument

More information

Synthesis, Isolation, and Purification of an Ester

Synthesis, Isolation, and Purification of an Ester Synthesis, Isolation, and Purification of an Ester AP Chemistry Laboratory Introduction An ester is a chemical compound that is formed when an organic acid reacts with an alcohol. Esters frequently have

More information

ORGANIC LABORATORY TECHNIQUES 10 10.1. NEVER distill the distillation flask to dryness as there is a risk of explosion and fire.

ORGANIC LABORATORY TECHNIQUES 10 10.1. NEVER distill the distillation flask to dryness as there is a risk of explosion and fire. ORGANIC LABORATORY TECHNIQUES 10 10.1 DISTILLATION NEVER distill the distillation flask to dryness as there is a risk of explosion and fire. The most common methods of distillation are simple distillation

More information

Laboratory 14. Vapor Pressure and the Heat of Vaporization. Objectives. Introduction

Laboratory 14. Vapor Pressure and the Heat of Vaporization. Objectives. Introduction Laboratory 14 Vapor Pressure and the Heat of Vaporization Objectives Use experimental techniques to record temperature and volume data for known and unknown compounds in which the liquid and gas are in

More information

Experiment 2: Recrystallization & Melting Point

Experiment 2: Recrystallization & Melting Point Experiment 2: Recrystallization & Melting Point Part A: Choosing a Solvent Part B: Purification of Phenacetin Reading: Mohrig, Hammond & Schatz Ch. 15 pgs 183-197 Ch. 10 pgs 104-113 Ch. 14 pgs 174-182

More information

Determination of the Molar Mass of an Unknown Solid by Freezing Point Depression

Determination of the Molar Mass of an Unknown Solid by Freezing Point Depression Determination of the Molar Mass of an Unknown Solid by Freezing Point Depression GOAL AND OVERVIEW In the first part of the lab, a series of solutions will be made in order to determine the freezing point

More information

2.1 Properties of Matter > Chapter 2 Matter and Change. 2.1 Properties of Matter. 2.2 Mixtures 2.3 Elements and Compounds 2.4 Chemical Reactions

2.1 Properties of Matter > Chapter 2 Matter and Change. 2.1 Properties of Matter. 2.2 Mixtures 2.3 Elements and Compounds 2.4 Chemical Reactions 21 Properties of Matter > 1 Copyright Pearson Education, Inc, or its affiliates All Rights Reserved Chapter 2 Matter and Change 21 Properties of Matter 22 Mixtures 23 Elements and Compounds 24 Chemical

More information

Warm-Up 9/9. 1. Define the term matter. 2. Name something in this room that is not matter.

Warm-Up 9/9. 1. Define the term matter. 2. Name something in this room that is not matter. Warm-Up 9/9 1. Define the term matter. 2. Name something in this room that is not matter. Warm-Up 9/16 1. List the three most important rules of lab safety. 2. Would you classify jello as a solid or a

More information

EXPERIMENT 1 - Determination of the purity and identity of organic compounds by melting point and/or analytical thin layer chromatography

EXPERIMENT 1 - Determination of the purity and identity of organic compounds by melting point and/or analytical thin layer chromatography EXPERIMENT 1 - Determination of the purity and identity of organic compounds by melting point and/or analytical thin layer chromatography PART A Melting points and mixed melting points. As discussed in

More information

Evaluation copy. Fractional Distillation. computer OBJECTIVES MATERIALS

Evaluation copy. Fractional Distillation. computer OBJECTIVES MATERIALS Fractional Distillation Computer 8 An example of a simple distillation is the separation of a solution of salt and into two separate pure substances. When the salt solution is heated to boiling, vapor

More information

Reminder: These notes are meant to supplement, not replace, the laboratory manual. Refractive Index

Reminder: These notes are meant to supplement, not replace, the laboratory manual. Refractive Index Reminder: These notes are meant to supplement, not replace, the laboratory manual. Refractive Index History and Application: The type of refractometer instrument you are using today i has been commercially

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

Purification by Recrystallization

Purification by Recrystallization Experiment 2 Purification by Recrystallization Objectives 1) To be able to select an appropriate recrystallizing solvent. 2) To separate and purify acetanilide by recrystallization. 3) To compare the melting

More information

Figure 1. Simple Phase Diagram for a Two-Component Mixture

Figure 1. Simple Phase Diagram for a Two-Component Mixture rganic Chemistry I Laboratory Recrystallization, Melting Point, and Chromatography: Experiment 2 Separating and Identifying the Components of a Mixture 1 Week 2 Background Reading Zubrick, J. W. The rganic

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

GAS LAWS. Lab #10 PROCEDURE: Part A: Charles Law:

GAS LAWS. Lab #10 PROCEDURE: Part A: Charles Law: GAS LAWS In 1660, Robert Boyle, an English philosopher, performed an experiment in which he showed that the volume of a trapped amount of air varied inversely with the pressure applied to it. However,

More information

Interpretation of Experimental Data

Interpretation of Experimental Data Lab References When evaluating experimental data it is important to recognize what the data you are collecting is telling you, as well as the strengths and limitations of each method you are using. Additionally,

More information

Chapter 12 - Liquids and Solids

Chapter 12 - Liquids and Solids Chapter 12 - Liquids and Solids 12-1 Liquids I. Properties of Liquids and the Kinetic Molecular Theory A. Fluids 1. Substances that can flow and therefore take the shape of their container B. Relative

More information

INVESTIGATING SOLUTIONS. Pre-Lab Queries. Procedure

INVESTIGATING SOLUTIONS. Pre-Lab Queries. Procedure NAME PARTNER(S) SECTION DATE INVESTIGATING SOLUTIONS The objective of this activity is to uncover characteristics of a variety of solutions and factors that affect the making of solutions. Pre-Lab Queries

More information

COLUMN CHROMATOGRAPHY EXTRACTION OF PIGMENTS FROM SPINACH (THIS LABORATORY PROCEDURE WAS PROVIDED BY Dr. V. WAGHULDE.)

COLUMN CHROMATOGRAPHY EXTRACTION OF PIGMENTS FROM SPINACH (THIS LABORATORY PROCEDURE WAS PROVIDED BY Dr. V. WAGHULDE.) COLUMN CHROMATOGRAPHY EXTRACTION OF PIGMENTS FROM SPINACH (THIS LABORATORY PROCEDURE WAS PROVIDED BY Dr. V. WAGHULDE.) Purpose: To separate plant pigments from spinach leaves using column chromatography.

More information

Heats of Transition, Heats of Reaction, Specific Heats, and Hess s Law

Heats of Transition, Heats of Reaction, Specific Heats, and Hess s Law Heats of Transition, Heats of Reaction, Specific Heats, and Hess s Law GOAL AND OVERVIEW A simple calorimeter will be made and calibrated. It will be used to determine the heat of fusion of ice, the specific

More information

Determining the Quantity of Iron in a Vitamin Tablet. Evaluation copy

Determining the Quantity of Iron in a Vitamin Tablet. Evaluation copy Determining the Quantity of Iron in a Vitamin Tablet Computer 34 As biochemical research becomes more sophisticated, we are learning more about the role of metallic elements in the human body. For example,

More information

Aspirin Synthesis H 3 PO 4

Aspirin Synthesis H 3 PO 4 Aspirin Synthesis Experiment 5 Aspirin is the common name for the compound acetylsalicylic acid, widely used as a fever reducer and as a pain killer. Salicylic acid, whose name comes from Salix, the willow

More information

Review - After School Matter Name: Review - After School Matter Tuesday, April 29, 2008

Review - After School Matter Name: Review - After School Matter Tuesday, April 29, 2008 Name: Review - After School Matter Tuesday, April 29, 2008 1. Figure 1 The graph represents the relationship between temperature and time as heat was added uniformly to a substance starting at a solid

More information

Water Lab. Objective: To distill samples of water that contains volatile and nonvolatile components.

Water Lab. Objective: To distill samples of water that contains volatile and nonvolatile components. Water Lab I. Distillation Hypothesis: Water can be purified by distillation. Objective: To distill samples of water that contains volatile and nonvolatile components. Materials and Equipment: Sodium chloride,

More information

Determination of Molar Mass by Boiling Point Elevation of Urea Solution

Determination of Molar Mass by Boiling Point Elevation of Urea Solution Determination of Molar Mass by Boiling Point Elevation of Urea Solution CHRISTIAN E. MADU, PhD AND BASSAM ATTILI, PhD COLLIN COLLEGE CHEMISTRY DEPARTMENT Purpose of the Experiment Determine the boiling

More information

MOLECULAR WEIGHT BY BOILING POINT ELEVATION

MOLECULAR WEIGHT BY BOILING POINT ELEVATION MOLECULAR WEIGHT BY BOILING POINT ELEVATION BACKGROUND This experiment demonstrates the use of colligative properties. The goal is to measure the molecular weight of a non-volatile solute by determining

More information

21 st Century Chemistry Structured Question in Topic 1 Planet Earth Unit 1-4

21 st Century Chemistry Structured Question in Topic 1 Planet Earth Unit 1-4 21 st Century Chemistry Structured Question in Topic 1 Planet Earth Unit 1-4 1. Air consists of oxygen and other substances. (a) Is oxygen an element or a compound? Explain briefly. It is an element. [1]

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

Test 1: Introduction to Chemistry

Test 1: Introduction to Chemistry Name: Sunday, October 14, 2007 Test 1: Introduction to Chemistry 1. Two substances, A and Z, are to be identified. Substance A can not be broken down by a chemical change. Substance Z can be broken down

More information

1º ESO UNIT 3: Pure substances and mixtures. Susana Morales Bernal

1º ESO UNIT 3: Pure substances and mixtures. Susana Morales Bernal 1º ESO UNIT 3: Pure substances and mixtures Objectives 1. To know that a substance is identified according to its characteristic properties like: density and melting or boiling points. 2. To know the concepts

More information

THERMOMETER CALIBRATION USING CONTROLLED TEMPERATURE BATHS

THERMOMETER CALIBRATION USING CONTROLLED TEMPERATURE BATHS Test Procedure for THERMOMETER CALIBRATION USING CONTROLLED TEMPERATURE Texas Department of Transportation TxDOT Designation: Tex-926-K Effective Date: August 1999 1. SCOPE 1.1 Calibrate thermometers by

More information

Recrystallization Introduction Solubility

Recrystallization Introduction Solubility 1 Recrystallization Introduction Solubility Most compounds are more soluble in a given solvent at higher temperatures. As you can see from the data in the table below, the solubilities in water of salt

More information

UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS International General Certifi cate of Secondary Education

UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS International General Certifi cate of Secondary Education www.smarteduhub.com UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS International General Certifi cate of Secondary Education *0367948514* CHEMISTRY 06/61 Paper 6 Alternative to Practical May/June 12

More information

Chem 112 Intermolecular Forces Chang From the book (10, 12, 14, 16, 18, 20,84,92,94,102,104, 108, 112, 114, 118 and 134)

Chem 112 Intermolecular Forces Chang From the book (10, 12, 14, 16, 18, 20,84,92,94,102,104, 108, 112, 114, 118 and 134) Chem 112 Intermolecular Forces Chang From the book (10, 12, 14, 16, 18, 20,84,92,94,102,104, 108, 112, 114, 118 and 134) 1. Helium atoms do not combine to form He 2 molecules, What is the strongest attractive

More information

A Beer s Law Experiment

A Beer s Law Experiment A Beer s Law Experiment Introduction There are many ways to determine concentrations of a substance in solution. So far, the only experiences you may have are acid-base titrations or possibly determining

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

Apparatus error for each piece of equipment = 100 x margin of error quantity measured

Apparatus error for each piece of equipment = 100 x margin of error quantity measured 1) Error Analysis Apparatus Errors (uncertainty) Every time you make a measurement with a piece of apparatus, there is a small margin of error (i.e. uncertainty) in that measurement due to the apparatus

More information

Unit 1 Review. 4. Which state of matter is characterized by having a low density and high compressibility? a. solid b. liquid c. gas d.

Unit 1 Review. 4. Which state of matter is characterized by having a low density and high compressibility? a. solid b. liquid c. gas d. Unit 1 Review Keys to Success: 1. Review syllabus goals and key terms. 2. Review class notes for Unit 1. 3. Review all homework. 4. Complete review, check answers, and come in for extra help to clarify

More information

Lead/Tin Solder Lab. 1. Select a labeled cup(s) and sign your names on the table of lead/tin percentages.

Lead/Tin Solder Lab. 1. Select a labeled cup(s) and sign your names on the table of lead/tin percentages. Lead/Tin Solder Lab 1. Select a labeled cup(s) and sign your names on the table of lead/tin percentages. 2. Mass out 50 grams total of your assigned lead and tin alloy. 3. Melt the metals together in an

More information

Experiment 3 Introduction to Density INTRODUCTION

Experiment 3 Introduction to Density INTRODUCTION Experiment 3 Introduction to Density INTRODUCTION The purpose of this experiment is to understand the meaning and significance of the density of a substance. Density is a basic physical property of a homogeneous

More information

Laboratory Exercise: Calibration of a Thermometer

Laboratory Exercise: Calibration of a Thermometer CHEM 109 Introduction themistry Revision 3.1 Laboratory Exercise: Calibration of a Thermometer In this exercise we will calibrate a stem-type thermometer and then use it to correctly measure the Air temperature

More information

PHYS 3324 Experiment 2: Atomic Spectra

PHYS 3324 Experiment 2: Atomic Spectra PHYS 3324 Experiment 2: Atomic Spectra Background Reading: Krane, pp. 185-189 Apparatus: Spectrometer, sodium lamp, hydrogen lamp, mercury lamp, diffraction grating, watchmaker eyeglass, small flashlight.

More information

Physical and Chemical Properties

Physical and Chemical Properties Physical and Chemical Properties Introduction Matter can be classified in different ways using physical and chemical properties. Physical properties include color, odor, density, hardness, structure, solubility,

More information

Experiments that focus on extracting pigments from plants have long been

Experiments that focus on extracting pigments from plants have long been Extraction and Thin-Layer Chromatography of Chlorophyll A and B from Spinach Adapted by R. McLaughlin and K. Masters from Griffin, G. William; Quach, Hao T.; Steeper, Robert L. J. Chem. Ed. 2004, 81, 385-387;

More information

Investigation M3: Separating Mixtures into Component Parts

Investigation M3: Separating Mixtures into Component Parts Investigation M3: Separating Mixtures into Component Parts Goals: Use various methods to separate mixtures, make inferences from temperature/time graphs, and identify substances. 81 Activity M3.3: What

More information

Fractional Distillation and Gas Chromatography

Fractional Distillation and Gas Chromatography Fractional Distillation and Gas Chromatography Background Distillation The previous lab used distillation to separate a mixture of hexane and toluene based on a difference in boiling points. Hexane boils

More information

INVESTIGATION OF THE COLLIGATIVE PROPERTIES OF FATTY ACIDS

INVESTIGATION OF THE COLLIGATIVE PROPERTIES OF FATTY ACIDS INVESTIGATION OF THE COLLIGATIVE PROPERTIES OF FATTY ACIDS INTRODUCTION FATTY ACIDS Fatty acids play a relevant role in our daily life. Fatty acids are long chain hydrocarbons with a terminal carboxyl

More information

Chemistry 212. Density

Chemistry 212. Density Chemistry 212 Density LEARNING OBJECTIVES To study density as a method of identification. To determine the densities of regularly and irregularly shaped solids as well as of pure liquids and solutions.

More information

EXPERIMENT 4. This lab will meet on Monday October 22 nd and Tuesday October 23 rd in Science Center 210.

EXPERIMENT 4. This lab will meet on Monday October 22 nd and Tuesday October 23 rd in Science Center 210. EXPERIMENT 4 Synthesis and Analysis of CdSe Quantum Dot Nanocrystals This lab will meet on Monday October 22 nd and Tuesday October 23 rd in Science Center 210. Before You Come to Lab: Read the entire

More information

Phase change lab questions Period: Physical Science

Phase change lab questions Period: Physical Science Phase change lab questions Period: Physical Science Name: Date: Pre-lab: (As always, write in complete sentences) 1. What should happen to the temperature of a substance while the substance is melting?

More information

Determination of Molecular Mass by Freezing Point Depression

Determination of Molecular Mass by Freezing Point Depression Determination of Molecular Mass by Freezing Point Depression Objectives: To determine the molecular mass of an unknown solid using the colligative property of freezing point depression. Background: When

More information

Combusting Candles. Category: Chemistry Type: Class Experiment (60 min) Materials List: Be careful! This activity involves working with open flames.

Combusting Candles. Category: Chemistry Type: Class Experiment (60 min) Materials List: Be careful! This activity involves working with open flames. Combusting Candles Category: Chemistry Type: Class Experiment (60 min) Materials List: 2 Tealight candles 1 Nail 1 Glass Jar with a flat top, e.g jam jar 1 Lighter or matches Video: (youtubelink) Be careful!

More information

Description: Vocabulary: Objectives: Materials: Safety:

Description: Vocabulary: Objectives: Materials: Safety: Title: Spectral Analysis with DVDs and CDs Author: Brendan Noon Date Created: Summer 2011 Subject: Physics/Chemistry/Earth Science Grade Level: 9-12 Standards: Standard 1: Analysis, Inquiry, and Design

More information

The Decomposition of Potassium Chlorate

The Decomposition of Potassium Chlorate The Decomposition of Potassium Chlorate Small quantities of molecular oxygen (O 2 ) can be obtained from the thermal decomposition of certain oxides, peroxides, and salts of oxoacids. Some examples of

More information

Bomb Calorimetry. Electrical leads. Stirrer

Bomb Calorimetry. Electrical leads. Stirrer Bomb Calorimetry Stirrer Electrical leads Oxygen inlet valve Bomb Fuse Calorimeter Outer jacket Not shown: heating and cooling system for outer jacket, and controls that keep the outer jacket at the same

More information

Percent Composition of Hydrates

Percent Composition of Hydrates Name Class Date Percent Composition of Hydrates You are a research chemist working for a company that is developing a new chemical moisture absorber and indicator. The company plans to seal the moisture

More information