HomeClass Notes1,200,000US530,000

CHEM 1062 Lecture Notes - Lecture 1: Miscibility, Sodium Chloride, Freezing-Point Depression

28 views3 pages

indigoraccoon472

27 Sep 2016

School

Department

Course

Professor

For unlimited access to Class Notes, a Class+ subscription is required.

Document Summary

Solution = homogeneous mixture of 2 or more chemicals, 1 phase uniform distributions of molecules throughout. Gas in a liquid = oxygen in water. Solid in liquid = salt in water (ionic) Gas in gas = air; all gases infinitely soluble in each other. Colloidal suspensions = not solutions, very stable suspensions of very fine particles (nanometer) Do not settle in the liquid because of brownian motion of liquid molecules. Example: milk, nano particles of fat & proteins. Molarity (m) = number of moles of solute / volume usually in l of solution (total volume) Molality (m) - moles of solute / mass of solvent ; this does not depend on temperature. Percent- weight by weight = (mass of solute / mass of solution) * 100. Mass of solution = mass of solute + mass of solvent. Percent- volume by volume = (volume of solute / volume of solution) * 100.

Related textbook solutions

Chemistry: Structure and Properties

ISBN: 9780134293936

Basic Chemistry

ISBN: 9780134138046

Principles of Chemistry Molecular Approach

ISBN: 9780134112831

Principles of Chemistry Molecular Approach

3rd Edition, 2014

ISBN: 9780321971944

Chemistry: Structure and Properties

ISBN: 9780134293936

Chemistry: A Molecular Approach

ISBN: 9780321809247

Chemistry: A Molecular Approach

ISBN: 9780134874371

Principles of Chemistry: A Molecular Approach

ISBN: 9780134895741

Chemistry: The Central Science

14th Edition, 2017

ISBN: 9780134414232

Related Documents

CHEM 1062 Chapter 13: Chem 1602 Notes ch 13

CHEM 1062 Chapter Notes - Chapter 13: Mole Fraction, Boiling-Point Elevation, Partial Pressure

indigoraccoon472

CHEM 1062 Lecture Notes - Lecture 3: Boiling-Point Elevation, Colligative Properties, Mole Fraction

cerisegiraffe538

Related Questions

I can't seem to figure this one out. thank you!

BAEDitemViewlassignmentProblemiD-830644918offset next 121C1 12 Introduction to Solutility and Solution Formation troduction to Solubility and Solution Formation arning Goal understand the solubility of a solute in a solvent, the dissoltion p peocess, and the properties that afect the rate of dissoluÅ¡on ocess, and the properties that affed the rate of cola has a certain amount of carbon dioxide dissolved in t The cola is theretore olecular level, the dissolution process involves breaking intermolecular forces of aty action rious parameters, such as temperature, pressure, the nature of the solute, and the r example an incresse in temperature may increase the rate of dissoludon for solutions hwolving solds an example of a solution of gas in waler. The carbon daxide gas is the solute and it is diessved in water,which is nature of the solvent One can increase or decrease the solubility of solute by changing hese parameters e f the solvere At the among the solute molecules and forming new ones with the solvent moleciles The solublty af a solute in a salent depend art A The properties of a solute and its solubility in liquid solvents A solution is a homogenous mixture of solute and solvent There are diHarent types of soluions. A carbonated drink ia an example of a solution where the solute is a gas and ths saveet is a iquid Sugar crystas a in water is an example of a solution where the solute is a solid and the solvent is liquid Aceic acid is miscible in water, forming a solution commonly known as vinegar ln this case both the solure and the sohen iquids The solubility of solute in a solvent depends on various parsmeters, such as temperature pressura, tha nature of the solute, and the nature of the salvent Considaring thesa paranters iderdfy the ts correct for the solublity of a solute in a solvent Check all that apply Hints Table salt dissolves in water to form a solution Zinc sullate is soluble in water Gases are readly soluble in water t higher tamperatures Carbon dioxide gas will be more soluble in water when the partial pressure is high Propanol and heptane are miacible Dei My Awers Give Up

Please help me solve for the molar mass of sample 1 and 2 and the molecular formula

Experiment 1084-03: Determination of M.M. by Freezing Point Depres sion Measure the freezing-point depressions solute whose empirical formula is known Pool the class hat occur with solutions containing mass of the solute and its Background Information However, as soon as the solution begins to freeze, Adding a solute to a pure, non-volatile lquid ature will remain constant untl all the (solvent) lowers the vapor pressure of the solvent raises its boiling point, and lowers (depresses) its freezing point. The extent to which these are aftected depends on the relative number of solute particlos in the solution. Properties of solutions that depend only on the number of solute molecules in a given quantity of solvent are called colligative properties. Such cyclohexane turns into solid. Once the substance again. The freezing point is the temperature where it stays constant, Le. the liquld phase and the sold phase of the cyclohexane coexists (Figure 3-1) boiling point elevation and osmotic pressure. They do NOT dopend on the nature of the solute, but DO depend on the nature of the solvent. As a consequence, colligative properties can be used to determine an unknown molar mass for a solute. In this experiment, we will be using cyclohexane (d " 0.779 gmL, K, . 20.5 oC/m) as the solvent to determine the molar mass of a white solid with an empirical formula of C,HC. The freezing point depression, Î7, is the difference between the freezing point of the pure solvent, TP, and the freezing point of the solution (solvent and solute). T As mentioned above, thits quantity is proportional only to the molal concentration of the solute, m Figure 3-1. Cooling Curves The proportionality constant, K, is called the freezing-point-depression constant. The K value of 20.5 C/m for Cyclohexane is one of the largest values one can find. Molal concentration is defined as the number of moles of substance in 1 kg of solvent. Now we can calculate the molar mass of a solute from ATã K,, the mass of the The freezing point of a solution in cyclohexane can be obtained in a similar way. Cooling results in an initial rapid decrease in the temperature until freezing begins as seen in the cooling curve of the pure solvent. However, the temperature of the solution does not remain constant while being frozen. As the cyclohexane in the solution treezes, cyclohexane is taken away from the solution and the concentration of the solute becomes higher In the liquid portion. Thus the molal concentration of the solute increases and the freezing point of the solute and the mass of the solvent. remaining liquid becomes lower. The result is a steadily decreasing freezing temperature until the solution is completely frozen. When all the solution In order to determine ATP, we will measure the freezing point of pure cyclohexane and the freezing point of a solution of the solute in is frozen, the temperature decreases more rapidly To evaluate the freezing point of pure cyclohexame, you will cool a sample of this substance, and measure the temperature as a The freezing point of the solution is the temperature at which the solution starts to freeze. portion represents the concentration of the starting function of time. As cooling begins, theOnly at this point, the concentration of the liquid temperature of the cyclohexane decreases rapidly.

Experiment 10 Colligative Properties Introduction A pinch of wa make boiling water hotter. A handful will clear the snow from your steps. Every day we the physical properties of materials around us, but often don't know why we use these particular s or what chemistry is involved. Modifying the temperature of phase changes, by adding a second chemical to the pure solvent are examples of manipulating the Colligative Properties of a solution. this lab, we will study how varying the concentration and type of a salt affects the point of a solution. Colligative properties are properties of a solution containing 2 or more components. Typically, the primary is the solvent and the other called the such as color or hardness, properties depend on the number of particles of astute in the not the identity of the In many cases, the rokute will determine the number of solute particles (degree of ionization, solubility, etc,) in the solvent, but a colligative property does not depend upon the nature of the particles. Two colligative properties commonly encountered are boiling point elevation and freezing point depression (the temperature of of a is lower than of pure solvent). We will be studying boiling point elevation in this Most of the previous work that you have done with solutions has involved units of molarity, M, or moles of solute per liter of solution. Boiling point elevation calculations (as well as those for freezing point depression) or moles of solute per kilogram of solvent. boili change of temperature. When the temperature of a solution changes, the volume of the solution also changes. Since molarity depends on a change in wil the solution's molarity. Molality depends on the mass of the solvent. and thus is independent of temperature. n't Hoff Factor salt into and the of moles inorganic salts in an aque the based on the addition of the number dissociates, the total number of particles in the solution will be of cations and anions produced from the dissociation. Thus; Nacion Na Choaa (2moles of particles) Cacbrs Ca +2ch (3moles of particles) The quantity of particles produced per mole of solute is called the van'tHoff factor and is given the symbol, i, If 1 mole of sodium chloride were completely dissociated, iwould be 2. This theory works very well for dilute solutions and non-electrolytes (i 1, no dissociation at all since nonelectrolytes not ionize), For does not always apply to more concentrated solutions. Thus, when there are a large number of particles in a solution, they have a tendency to recombine as the salt and you don't get 100% dissociation. example, at a NaCl concentration of 0.1M, iwill be 1.81 (90% dissociation) rather than 2 (100%). Boiling Point Elevation solute causes the solution to boil at a higher When a solution is heated, the presence of a non-volatile point of the pure liquid and the temperature than the pure The difference between the boiling boiling point of the solution is: 169