A greener approach for measuring colligative properties. Colligative properties depend on the number of particles present in a solution, but not on the identity of the particles. Colligative properties of solutions depend on the concentration of solute particles but not on their identity. The lab report assistant is simply a summary of the experiment s questions, diagrams if needed, and data tables that should be addressed in a formal. Colligative properties are properties of a solvent, such as freezing point depression and boiling point elevation, which depend on the concentration of solute particles dissolved in the solvent.
The virtual lab is an online simulation of a chemistry lab. Colligative property an overview sciencedirect topics. So youve got to know, which things form azeotropes. Colligative properties are all dependent upon the molality m of a solution. This experiment focuses on the property of freezingpoint depression. Colligative properties determination of the molar mass of a compound by freezing point depression. The purposes of this experiment were to observe and measure the effect of a solute on the freezing point of a solvent and to determine the molar mass of the unknown solute labeled eagles. To complete this calculation, the mass of solute and solvent must be known as well as the freezing pointsboiling points of. Before you begin, save this lab report template on your computer as lastnameapchem4b.
The purpose of this experiment was to analyze the colligative properties, ones whose values depend only on the number of solute particles present, not on their chemical identity, of different solutions. Experiment on colligative properties boston university. The objective of this experiment is to determine the molar mass of an unknown solute by measuring the freezing point depression of a solution of this solute in a solvent as compared to the freezing point of the pure solvent. At least, everyday life during the wintertime or when boiling water and making pasta. There is a direct relationship between the boiling point elevation and the number of particles present in a solution. Freezing point depression lab add 6g of distilled water into test tube and submerge thermometer into it before putting it into a deep freeze. If so, you have already been exposed to a group of four physical phenomena called colligative properties. The properties that exhibit such changes are called the colligative properties and include. Since colligative properties do not depend on the nature of the solute, they may be used to determine the molecular weight of a substance. Freezingpoint depression and boilingpoint elevation. Since colligative properties do not depend on the nature of the solute, they may be used to determine the molecular weight of a.
Colligative properties include vapor pressure lowering, boiling point elevation, freezing point depression, and membrane. Chem 1252 lab report 3 lab partner n\a colligative. The four colligative properties that change as a result of the addition of solute are freezing point, boiling point, vapor pressure, and osmotic pressure. For example, if you added the same number of moles of sugar and salt, the salt would have a greater effect than the sugar because it is ionic. Colligative properties lab with an unusual problem. Colligative properties of solutions vernier vernier software. At this temperature, the gaseous and liquid states of. Still i have found colligative properties to be of great interest and still approach the topic qualitatively with my chemistry 2 and honors chemistry 2 students. Determination of the molar mass of a compound by freezing point depression. These characteristics are fully dependent on the number of particles dissolved in the solution it does not matter what those particles are. The cooling curves for the solutions were generally accurate, and resulted in a realistic molar mass, which means this lab was a success. Solute is the lesser component and solvent the greater component in a solution. If the number of particles is significant, colligative. The neat thing about them is that it doesnt matter what the solute is, just how much is there.
There are four colligative properties, and you already. Colligative properties of solutions presentation chemistry. Exploring freezing point depression using freeze pops. Lets talk about colligative properties solutions and colligative properties are a collection of physical properties of the solution that are affected by the number of solute particles. In chemistry, colligative properties are properties of solutions that depend on the ratio of the number of solute particles to the number of solvent molecules in a solution, and not on the nature of the chemical species present. Colligative properties include vapor pressure lowering, boiling point elevation.
The colligative properties include vapor pressure lowering, boiling point elevation, freezing point depression, and osmotic pressure. Freezingpoint depression to determine an unknown compound. Oct 30, 2016 colligative collective properties of solutions they are properties whose values depend only on the number of solute particles per unit volume of solution and not on the type of solute, collective properties of solutions are vapour pressure depression, boiling point elevation and freezing point depression. Investigating freezing point depression and cirrus cloud. Colligative properties are properties of solutions that depend on the number of particles in a volume of solvent the concentration and not on the mass or identity of the solute particles. I calculated the molar mass of my groups unknown sample to be 211. Colligative properties are dependent only on the number of particles in a solution, and not their identity. The four colligative properties that change as a result of the addition of solute are freezing point, boiling point, vapor pressure, and. To answer this, we need to understand the concept of colligative properties.
Learn vocabulary, terms, and more with flashcards, games, and other study tools. This lab activity is used to introduce colligative properties in solutions, concentrating primarily on the effects of nonvolatile solutes on freezing point. What was the objective of this experiment and how was it achieved. The greener procedure substitutes the nontoxic, noncarcinogenic compounds stearic, myristic, lauric, and palmitic acids for the less benign aromatic compounds p. A change in a property of a solvent that depends on the concentration of dissolved solutes particles is called a colligative property. Colligative properties lab freezing point depression. The boiling points of solutions are always higher, and the freezing points of solutions are always lower, than those of the pure solvent. Colligative properties freezing point depression lab format. Colligative properties are those that depend on the concentration of particles in a solution, not upon the identity of those particles. View notes colligative properties postlab from chemistry laboratory at high technology high sch. An ebook reader can be a software application for use on a computer such as microsofts free reader application, or a booksized computer this is used solely as a reading device such as nuvomedias rocket ebook. Colligative properties are also affected by temperature. There are many materialssolutions that adding more of something will always result in some consisten.
To complete this calculation, the mass of solute and solvent must be known as well as the freezing pointsboiling points of the pure solvent and the solution. The lab activity includes background information on colligative properties and how. Molality is defined as moles of solutekg of solvent. Historically, colligative properties have been one means. Colligative properties include changes in vapor pressure. When a solute dissolves in a solvent such as water, various physical properties are affected. The greener procedure substitutes the nontoxic, noncarcinogenic compounds stearic, myristic, lauric, and palmitic acids for the less benign aromatic compounds pdichlorobenzene, benzil, biphenyl, naphthalene, and nitrotoluene. To perform a second trial during the colligative properties lab, you can just remelt your first solution to obtain a second measurement. Colligative properties of solutions ideally depend only on the number of solute particles per solvent molecule and not on the nature of the solute or solvent. When a solute is added to water the physical properties of freezing point and boiling point change. The colligative property of freezing point depression was the theory at work behind what was observed in the experiment trials. Examples include the pressure of an ideal gas and the depression of the freezing point. The vapor pressure of a pure liquid at a given temperature is a characteristic property of that liquid.
Heres all the info for the lab writeup we have to do in class. So it implies that there is a collective effort to change properties of a pure liquid or solid. In the late nineteenth century the french chemist francois raoult noted that the vapor pressure of a pure. I scream, we all scream for colligative properties. Colligative properties freezingpoint depression and boilingpoint elevation computer simulation colligative properties of solutions. Experiment 14 lab report chem molar mass of of a solid studocu. Colligative propertiesstudent laboratory kit flinn scientific. I dont really understand how to do the analysis part, so any help would be really appreciated. The three colligative properties are boiling point, freezing point, and vapor. As a first step towards the greening of instructional laboratories, we present a new greener version of a laboratory procedure designed to measure colligative properties. Analysis the following are the calculations required for the analysis questions.
The purpose of this experiment was to determine the molar mass of an unknown, nonvolatile solute. The phenomenon of freezing point lowering will be examined. Colligative properties depend only on the number of dissolved particles that is, the concentration, not their identity. Please scroll below to find our collection of prewritten problems. Apr 14, 2009 heres all the info for the lab writeup we have to do in class. In this experiment, the lauric acidbenzoic acid solution will exhibit a more. Calculation of the properties only works perfectly for ideal solutions. The number ratio can be related to the various units for concentration of solutions, for example, molarity, molality, normality chemistry, etc. Mode of separation only difference to other hplc methods specialist detectors can be used to determine properties of the samples investigated special gpcsec software required to perform analysis. The number ratio can be related to the various units for concentration of solutions, for example, molarity, molality. Dissolved solute in pure liquid will change the physical property of the liquid, i.
D t km, where d t is the change in freezing or boiling point, k is a solventspecific constant, and m is the solutions molality. This activity is used in a general chemistry class consisting of juniors and seniors in high school and it is completed before any notes are given on the subject. We had to calculate the molar mass of an unknown fatty acid that had been added to stearic acid. Determine freezing point of each system examined from analysis of its cooling curve. Antifreeze is the realworld example of a colligative property. Overall, the colligative properties can be very useful in our everyday lives. Colligative properties by definition a colligative property is a solution property a property of mixtures for which it is the amount of solute dissolved in the solvent matters but the kind of solute does not matter. The lab report assistant is simply a summary of the experiment s questions, diagrams if needed, and data tables that should be addressed in a formal lab report. I am doing the data analysis and writing a lab report on a colligative properties experiment involving freezing point depression. In chemistry, colligative properties are those properties of solutions that depend on the ratio of the number of solute particles to the number of solvent molecules in a solution, and not on the nature of the chemical species present.
The theory and experiment showed conclusively that polymer solutions do. The colligativeproperty law can be expressed using the equation. Robin furslund october, 2016 introduction introduced in 1891 by wilhelm ostwald the word colligative classified solute properties into three categories one being colligative properties. Lab 2 ice cream chemistry there are many chemical properties that have been utilized by humans in order to suit our own needs. After finding many articles on antifreeze, i decided to research more into the subject. Alternatively, a colligative property is a measure of the depression of the activity of the solvent in solution, compared to the pure state. Jul 29, 2016 colligative properties by definition are cases where the concentration of a solute not necessarily what the solute is is related to the effect. One of these properties that we have many uses for is a property known as colligative properties. How does antifreeze lower the freezing point of water in the cooling systems of automobiles.
The more, or less, of a solute that is present in ratio with the solvent will affect the calculations of the four colligative properties outlined above. Technology is used to collect, graph and analyze both the cooling of a pure solvent and the cooling of the. Dt kmolality use these to determine molar masses of solutes. In this experiment we will use the colligative property of freezing point.
Lab report 4 ch 204 introduction to chemical practice. Conclusion the purpose of this experiment was to determine. Health professions and related clinical sciences 51. This document is not meant to be a substitute for a formal laboratory report. Colligative properties of solutions properties depending on number of particles ions, molecules dissolved. These properties include boiling point elevation, freezing point depression, and osmotic pressure. Experiment on colligative properties colligative properties are the properties of solutions that depend on the total concentration of solute particles in solution. Colligative properties of solutions chemistry tutorial. In the colligative properties chemistry laboratory kit, students measure boiling points to determine how the concentration of a solution changes due to osmosis. Datamate program, students will then select the region shown above as. When the vapor pressure of a solvent is equal to atmospheric pressure, the solvent boils. Version 4201490001 lab report assistant this document is not meant to be a substitute for a formal laboratory report. Determination of molar mass by freezing point depression using paradichlorobenzene introduction.
Colligative properties are dependent on the ratio of solute and solvent particles in a. Colligative properties in real life chemical education. The colligative property of freezing point depression was the theory at work behind. Freezing point depression is one of the colligative properties of solutions discussed in this unit. An ebook reader can be a software application for use on a computer such as microsofts free reader. Chemists exploit the phenomenon of freezingpoint depression in the analysis of solid organic compounds. Aug 25, 2019 this lab activity is used to introduce colligative properties in solutions, concentrating primarily on the effects of nonvolatile solutes on freezing point. A pure substance in liquid or solid form will have certain properties such as a certain melting or boiling point.
Like pure solids, liquids and gases, solutions have welldefined physical properties e. Dissociationwhen neutral combinations of particles separate into ions while in aqueous solutionup to this point you have only thought about solution as a particle dissolved in water. However, when a nonvolatile solute is dissolved in the liquid, the vapor pressure of the liquid is reduced. The lab allows students to select from hundreds of standard reagents aqueous and manipulate them in a manner resembling a real lab. Colligative collective properties of solutions science. Analysis 2000 software was utilized to aid in the determination.
The physical properties of solutions that depend on the number of dissolved solute particles and not their specific type are known as colligative properties. Such properties are called colligative properties of the solution. The vapor pressure is the escaping tendency of solvent molecules. Experiment 14 lab report chem molar mass of of a solid. Colligative properties reflect the chemical potential of the solvent in solution. Colligative properties equations and formulas examples. Any questions on azeotropes, before we get to colligative properties.
Raoults law is concerned with the vapour pressure depression of solutions. Colligative properties such as freezing point depression or boiling point elevation can be used to calculate the molecular weight of a soluble solid. Jul 03, 2009 a presentation discussing the main colligative properties of solutions, applicable for high school chemistry or ap chemistry slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Freezingpoint depression, a colligative property, is investigated. So properties of solutions are going to be different from the properties of the actual solvent by itself.
The colligative properties of solutions strand phases of matter and kinetic molecular theory topic investigating properties of matter primary sol ch. Colligative properties equations and formulas examples in. Colligative properties of solutions such as freezing point. Colligative properties postlab analysis the following are.
Colligative properties depend on the lowering of the escaping tendency of solvent particles by the addition of solute particles. Some examples of colligative properties are vapor pressure, boiling point, freezing point, and osmotic pressure. Colligative properties are based on the amount of a substance not what it is. This laboratory experiment is appropriate for students enrolled in upper division atmospheric science. Colligative properties include changes in vapor pressure, boiling point, freezing point, and osmotic pressure.