ADSORPTION OF ACETAMINOPHEN ON ACTIVATED CHARCOAL
|
|
- Nicholas Sanders
- 7 years ago
- Views:
Transcription
1 Surface phenomena AIM ADSORPTION OF ACETAMINOPHEN ON ACTIVATED CHARCOAL The aim of the experiment is to analyze the adsorption process of acetaminophen on activated charcoal. Spectrophotometry is used to determine the concentration of paracetamol in solution before and after adsorption process on activated charcoal. The obtained results will serve to verify if the Freundlich isotherm can be used for quantitative description of the adsorption of acetaminophen on activated charcoal. REQUIRED KNOWLEDGE Adsorption ad solid interfaces, physical and chemical adsorption, adsorption isotherms (Langmuir, Freundlich and BET), hysteresis phenomena, adsorbents. INTRODUCTION The attachment of particles to a surface is called adsorption. The substance that adsorb is called the adsorbate. The adsorbate attaches to the surface of the solid substance that is called adsorbent. The reverse of adsorption is desorption. Adsorption of material at solid surfaces can take place from either adjacent liquid or gas phase. Molecules and atoms can attach to surfaces in two ways. Considering the nature of those interactions, the adsorption process is classified as physical adsorption (physisorption) and chemical adsorption (chemisorption). It is important to note that there are several differences between physical and chemical adsorption: The physisorption is associated with van der Waals interactions or hydrogen bonds that are weak but have a long range. In chemisorption, the adsorbate is sticked to the adsorbent by forming a chemical bond (usually a covalent one). Therefore, the chemical adsorption is considered to be the specific process. The energy released as the chemisorption occurs is much greater when compared to physical adsorption. The physical adsorption is an exothermic process. Therefore, when the temperature increases the physisorption decreases (the desorption takes place). In opposite, increase in temperature results in increasing chemisorption. The physical adsorption is reversible (desorption can take place). In the case of chemical adsorption, it is assumed that it is irreversible (it is very difficult to break the chemical bonds). In chemical adsorption, due to specific chemical bonds, only monolayer coverage of the adsorbent is possible. Monolayer formation is rare in physisorption where formation of several layers of adsorbate molecules on adsorbent surface is more common. Adsorption isotherms are the equations that describe mathematically the equilibrium state between an adsorbate and a solid surface (adsorbent) at constant temperature. They represent the amount of the adsorbate on the adsorbent as a function of its pressure (if gas) or concentration (if liquid) at constant temperature. The quantity adsorbed is nearly always normalized by the mass of the 1
2 adsorbent to allow comparison of different materials. Those equations can be derived theoretically (assuming the specific model of adsorption process) or empirically (considering experimental data). The Langmuir isotherm Irving Langmuir presented the simplest adsorption isotherm. It is a semi-empirical isotherm derived from a proposed kinetic mechanism. It is based on following assumptions: Adsorption cannot proceed beyond monolayer coverage. The surface of the adsorbent is uniform, that is, all the adsorption sites are equivalent. There are no interactions between adsorbed molecules. The Langmuir isotherm describes the variation of fractional coverage ϴ with pressure at constant temperature (derivation of Langmuir isotherm is presented in Appendix): (1) where: ϴ - fractional coverage (the ratio of a number of adsorption sites occupied and a number of adsorption sites available on the surface) K - constant value; the ratio of adsorption rate constant and desorption rate constant p - gas pressure Replacing ϴ by a/a m where a is the mass of gas adsorbed per gram of adsorbent at pressure p and at constant temperature and a m is the mass of gas that 1 gram of adsorbent can adsorb when monolayer is complete gives the formula: (2) The plot reflecting Langmuir isotherm: Figure 1. The Langmuir isotherm. It is characteristic that in the initial part of the graph (at low pressure) the directly proportional increase in adsorption with increasing pressure takes place. Then, with the increasing pressure of adsorbate (if gas), all the sites available for adsorption at the surface are occupied. Thus, despite the 2
3 further increase in pressure, the adsorption does not change because the entire surface of the adsorbent is occupied (and the Langmuir model assumed only the monolayer coverage). By inverting the equation (2) becomes: (3) A plot 1/a against 1/p yields a straight line and the a m and K values can be calculated from the slope and Y-intercept: Figure 2. Linear form of the Langmuir isotherm. The BET isotherm Often molecules do form multilayers, that is, some are adsorbed on already adsorbed molecules and then the Langmuir isotherm is not valid. Stephen Brunauer, Paul Emmett, and Edward Teller developed a model isotherm that takes that possibility into account. They considered that the initial adsorbed layer can act as a substrate for further adsorption. The BET isotherm serves as the basis for an important analysis technique for the measurement of the specific surface area of a material. (4) where: ϴ - fractional coverage (the ratio of a number of adsorption sites occupied and a number of adsorption sites available on the surface) C - a constant connected with the enthalpies of desorption from monolayer and vaporization of the liquid adsorbate Z - the ratio of the gas pressure (p) and the saturated vapour pressure (p*) 3
4 Figure 3. The BET isotherm. The Freundlich isotherm Freundlich gave an empirical expression representing the variation of adsorption of a quantity of substance adsorbed by unit mass of solid adsorbent with pressure (if adsorbate is a gas) or concentration (if the adsorbate is liquid) at constant temperature. In Freundlich model there is no assumption on monolayer coverage only, so it can describe multilayer adsorption process. The Freundlich isotherm equation is: where: (5) a - the mass of a substance adsorbed per gram of adsorbent k - the constant connected to adsorption energy; it is the adsorption value when the adsorbate concentration equals 1 mol/dm 3 n - the constant that reflects the interactions between adsorbate molecules p - gas pressure The Freundlich adsorption isotherm is a curve that reflects adsorption increase with increasing pressure: Figure 4. The Freundlich isotherm. 4
5 Constants k and n can be evaluated from linear form of Freundlich equation. Therefore, the decimal logarithms should be taken from equation (5). That gives: (6) The plot of loga against logp results a straight line where 1/n is a slope and logk is an Y-intercept. Figure 5. The linear form of the Freundlich isotherm. In the case of the adsorption from the solutions, the Freundlich isotherm becomes (c is a concentration of adsorbate in the solution): (7) The adsorption phenomenon is widely used in laboratory practice and in the industry. It is the basis of processes of purification, separation, analysis and isolation of compounds present in mixtures. Moreover, it plays a major role in adsorption chromatography. Several compunds used in treatment because of their strong abilities to adsorption. Medical charcoal (activated charcoal) is used as an universal antidote in reducing the effects of poisoning by the oral route. Activated charcoal and diosmectite are widely used in the treatment of diarrhea (they adsorb water, bacterial toxins and patogens such as bacteria or rotaviruses). From the other hand, adsorption may result in drug interactions when the molecules of one drug (eg. antihypertensive) are adsorbed on the surface of co-administered drug (eg. medical charcoal, antacid inorganic salts). It may cause the reduced effectiveness of pharmacotherapy. REFERENCES 1. Atkins P., de Paula J.: Physical pharmacy. Oxford University Press, Oxford Hermann T.W.: Farmacja fizyczna. Wydawnictwo Lekarskie PZWL, Warszawa Hermann T.W.: Chemia fizyczna. Wydawnictwo Lekarskie PZWL, Warszawa Atwood D., Florence A.T.: Physical pharmacy.pharmaceutical Press, London
6 EQUIPMENT AND MATERIALS Spectrophotometer UV-Vis Thermo-shaker Pipettes 0.1 M HCl Acetaminophen solution in 0.1 M HCl of concentration 12.5 mg/ml EXPERIMENTAL Acetaminophen solution in 0.1 M HCl of concentration 12.5 µg/ml Activated charcoal The task is to determine the acetaminophen concentration in solution (applying spectrophotometry) before and after adsorption (after 45-minute incubation of the drug with activated charcoal). 1. Prepare a series of 6 samples (in plastic tubes with the cap) that contain: Sample Mass of activated charcoal [mg] Volume [ml] of acetaminophen solution 12.5 mg/ml Volume of 0.1 M HCl [ml] blank Tightly close the tubes, vortex thoroughly and place in thermoshaker. Let the samples incubate for 45 minutes at the temperature 37 C. The speed of shaking should be stated at 700 cycles per minute. 3. During the incubation of samples with activated charcoal, prepare a calibration curve of absorbance against the concentration of acetaminophen in solution: a. Prepare a series of 6 samples that contain following acetaminophen concentrations: 12.5 µg/ml; 10.0 µg/ml; 7.5 µg/ml; 5.0 µg/ml; 2.5 µg/ml; 1.25 µg/ml. Use the stock solution of acetaminophen of concentration 12.5 µg/ml. Prepare the samples in 25 ml volumetric flasks by diluting the stock solution of paracetamol (12.5 µg/ml) with 0.1 M HCl solution. Consult the results obtained in calculations of volume of acetaminophen stock solution with the teacher. b. Measure the absorbance of the obtained solutions at λ max = 243 nm. Calibrate the spectrophotometer using 0.1 M HCl solution as a blank sample. c. Plot the calibration curve A = f (c) and determine the equation of a straight line (consult with the teacher the significance of the Y-intercept). 4. When the incubation is finished, remove the samples from the thermoshaker and centrifuge the samples for 10 minutes at 3500 rpm. 6
7 5. Prepare the appropriate dilutions of samples 1 4 (in volumetric flasks of 50 ml). For this purpose, measure out (using the pipette) the following volumes of the supernatant: Sample 1 (diluted 1000x) 0.05 ml (50 µl) Sample 2 (diluted 1000x) 0.05 ml (50 µl) Sample 3 (diluted 1000x) 0.05 ml (50 µl) Sample 4 (diluted 100x) 0.50 ml (500 µl) and fill up to 50 ml with 0.1 M HCl solution. 6. Measure the absorbance of the obtained solutions (after diluting) at λ max = 243 nm. The absorbance of the sample 5 shoud be measured directly (without diluting) by transferring to a cuvette about 3 ml of the supernatant. The spectrophotometer should be calibrated using the supernatant from the blank sample (without acetaminophen) transferred directly to the cuvette. Draw attention to not shake the sample and check if the obtained solution is clear (without particles of activated carbon) when pipetting the supernatant. If you notice any pollution in the supernatant, the sample should be centrifuged again and the clear supernatant should be collected. 7. Calculate the concentration of acetaminophen in samples after incubation with carbon using the equation of the calibration curve (the dilutions should be taken into account): where: c acetaminophen concentration at the equilibrium state (after incubation) [mg/ml] A absorbance b the Y-intercept of the calibration curve a the slope of the calibration curve R the sample dilution 8. Calculate the amount of acetaminophen (in mg): a. That was in the sample before incubation with activated charcoal b. That remained in the solution after incubation 9. Calculate the amount of adsorption a (how many mg of acetaminophen was adsorbed per 1 g of activated charcoal). 10. Plot the amount of adsorption a against acetaminophen concentration c (take into account the acetaminophen concentrations at the equilibrium state). Discuss the graph with the teacher. 11. Evaluate the linear Freundlich isotherm equation, calculate the values of k and n. Discuss with the teacher if Freundlich model is suitable for describing the process of acetaminophen adsorption on activated charcoal. 12. Analyze the amount of acetaminophen adsorbed on activated charcoal in the environment of the stomach (0.1 mol / l HCl) and at the temperature of human body. What clinical implications may 7
8 be related to co-administered acetaminophen and medical charcoal? Can the phenomenon of acetaminophen adsorption on activated charcoal be used in therapy? 13. Analyze the adsorption process in different temperature than 37 C (considering the results obtained from the teacher). Which type of adsorption (physical or chemical) is the binding of acetaminophen onto the activated charcoal? 8
9 LAB REPORT Acetaminophen adsorption on activated charcoal Purpose: 1. Calibration curve of absorbance against acetaminophen concentration in the solution. Sample Acetaminophen concentration [µg/ml] Absorbance (λ max = 243 nm) slope Y-intercept Calibration curve A = f(c) a b Y-intercept deviation Correlation coefficient S b r The final calibration curve equation (considering the Y-intercept significance):.. 2. The calculation of initial amount of acetaminophen in the samples that were further incubated with activated charcoal. Sample Acetaminophen concentration [mg/ml] Acetaminophen amount [mg]
10 Incubation time:.. Temperature of incubation:. Shaking speed: 3. The calculation of acetaminophen concentration in the samples at the equilibrium state (after incubation). Sample Absorbance (λ max =243 nm) dilution Acetaminophen concentration at the equilibrium state - c [mg/ml] 4. The calculation of the mass of acetaminophen adsorbed on activated charcoal. Sample Mass of activated charcoal Initial amount of acetaminophen in the sample amount of acetaminophen in the sample at the equilibrium state amount of acetaminophen adsorbed on 100 mg of activated charcoal [mg] [mg] [mg] [mg] a [mg/1g of charcoal] 5. The Freundlich isotherm equation (at the temperature 37 C). Sample c [mg/ml] logc a [mg/1g of charcoal] loga
11 Linear equation of Freundlich isotherm: Correlation coefficient r:.. Constant k:. Constant n:.. 6. The Freundlich isotherm equation (at the temperature.. C). Sample c [mg/ml] logc a [mg/1g of charcoal] loga Linear equation of Freundlich isotherm: Correlation coefficient r:.. Constant k:. Constant n:.. 7. Enclosures: Graph of the calibration curve A = f(c) Graph of the Freundlich isotherm a = f(c) Graph of the linear form of the Freundlich isotherm loga = f(logc) 8. Summary and conclusions: 11
EXPERIMENTAL METHODS IN COLLOIDS AND SURFACES
EXPERIMENTAL METHODS IN COLLOIDS AND SURFACES PARTICLE SURFACE AREA FROM GAS ADSORPTION TYPES OF ADSORPTION Physical adsorption: rapid, depends on adsorbate bulk concentration, multiple molecular layers
More informationAdsorption. December 2014
Adsorption December 2014 1 Nanosized objects have a large surface area Dividing the size of an object by 2... doubles the accessible surface 2 Adsorption Absorption Absorption is a phenomenon that occurs
More informationPhysical Chemistry Practical Course, Oxford University. Determination of the Surface Area of Alumina by Nitrogen Adsorption at 77K (4 points)
Physical Chemistry Practical Course, Oxford University 1.06 Determination of the Surface Area of Alumina by Nitrogen Adsorption at 77K (4 points) What you will do In this experiment you will study the
More informationHeterogeneous Catalysis and Catalytic Processes Prof. K. K. Pant Department of Chemical Engineering Indian Institute of Technology, Delhi
Heterogeneous Catalysis and Catalytic Processes Prof. K. K. Pant Department of Chemical Engineering Indian Institute of Technology, Delhi Module - 03 Lecture 10 Good morning. In my last lecture, I was
More informationSOLID STATE CHEMISTRY - SURFACE ADSORPTION
SOLID STATE CHEMISTRY - SURFACE ADSORPTION BACKGROUND The adsorption of molecules on the surfaces of solids is a very interesting and useful phenomenon. Surface adsorption is at the heart of such things
More informationDerivation of the BET and Langmuir Isotherms
Derivation of the BET and Langmuir Isotherms October 5, 2011 1 Langmuir Isotherm Assumptions used for the Langmuir isotherm 1. Gaseous molecules behave ideally 2. Only one monolayer forms 3. All sites
More informationBET Surface Area Analysis of Nanoparticles
OpenStax-CNX module: m38278 1 BET Surface Area Analysis of Nanoparticles Nina Hwang Andrew R. Barron This work is produced by OpenStax-CNX and licensed under the Creative Commons Attribution License 3.0
More informationTexture characteristic of membrane materials ASAP, BET
Texture characteristic of membrane materials ASAP, BET Theory Specific surface (surface area) is used for the characterization of many materials. There are various techniques how measure the specific surface
More informationEXPERIMENT 11 UV/VIS Spectroscopy and Spectrophotometry: Spectrophotometric Analysis of Potassium Permanganate Solutions.
EXPERIMENT 11 UV/VIS Spectroscopy and Spectrophotometry: Spectrophotometric Analysis of Potassium Permanganate Solutions. Outcomes After completing this experiment, the student should be able to: 1. Prepare
More informationpresented by Neal Leddy CMA Analytical Workshop 2012 SURFACE AREA AND POROSITY
presented by Neal Leddy CMA Analytical Workshop 2012 SURFACE AREA AND POROSITY Adsorption When a gas or vapour phase is brought into contact with a solid, part of it is taken up and remains on the outside
More informationMotivation Physisorption Chemisorption Outlook
Surface area determination - physisorption and chemisorption Literature: Motivation Physisorption Chemisorption Outlook 1. DIN ISO 9277: BET method 2. DIN 66136: Dispersion measurement of metals 3. DIN
More informationHiPer Ion Exchange Chromatography Teaching Kit
HiPer Ion Exchange Chromatography Teaching Kit Product Code: HTC001 Number of experiments that can be performed: 5 Duration of Experiment: Protocol: 5-6 hours Storage Instructions: The kit is stable for
More informationAdsorption and Catalysis
Adsorption and Catalysis Dr. King Lun Yeung Department of Chemical Engineering Hong Kong University of Science and Technology CENG 511 Lecture 3 Adsorption versus Absorption H H H H H H H H H Adsorption
More informationSpectrophotometry and the Beer-Lambert Law: An Important Analytical Technique in Chemistry
Spectrophotometry and the Beer-Lambert Law: An Important Analytical Technique in Chemistry Jon H. Hardesty, PhD and Bassam Attili, PhD Collin College Department of Chemistry Introduction: In the last lab
More informationPerforming Calculatons
Performing Calculatons There are three basic units for measurement in the organic laboratory mass, volume, and number, measured in moles. Most of the other types of measurements are combinations of them,
More informationOrganic Chemistry Calculations
Organic Chemistry Calculations There are three basic units for measurement in the organic laboratory mass, volume, and number, measured in moles. Most of the other types of measurements are combinations
More informationADSORPTION OF N2 ON SILICA GEL
Chapter 6. Adsorption of N 2 41 6 ADSORPTION OF N2 ON SILICA GEL The purpose of this experiment is to study the adsorption of gases on solid surfaces and to introduce you to some aspects of vacuum technique
More informationChapter Test B. Chapter: Measurements and Calculations
Assessment Chapter Test B Chapter: Measurements and Calculations PART I In the space provided, write the letter of the term or phrase that best completes each statement or best answers each question. 1.
More informationRemoval of Sulfate from Waste Water by Activated Carbon. Mohammed Sadeq Salman Computer Centre/ University of Baghdad
Al-Khwarizmi Engineering Journal, Vol. 5, No. 3, PP 72-76 (29) Al-Khwarizmi Engineering Journal Removal of Sulfate from Waste Water by Activated Carbon Mohammed Sadeq Salman Computer Centre/ University
More informationChem 405 Biochemistry Lab I Experiment 2 Quantitation of an unknown protein solution.
Chem 405 Biochemistry Lab I Experiment 2 Quantitation of an unknown protein solution. Introduction: The determination of protein concentration is frequently required in biochemical work. Several methods
More informationChemical reactions allow living things to grow, develop, reproduce, and adapt.
Section 2: Chemical reactions allow living things to grow, develop, reproduce, and adapt. K What I Know W What I Want to Find Out L What I Learned Essential Questions What are the parts of a chemical reaction?
More informationExperiment 2 Kinetics II Concentration-Time Relationships and Activation Energy
2-1 Experiment 2 Kinetics II Concentration-Time Relationships and Activation Energy Introduction: The kinetics of a decomposition reaction involving hydroxide ion and crystal violet, an organic dye used
More informationPHYSISORPTION DETERMINATIONS
G A S S O R P T I O N A N A L Y S I S PHYSISORPTION DETERMINATIONS Most atoms that make up a solid are bound on all sides by other atoms in the bulk of the solid. The atoms on the surface of the solid,
More informationMeasuring Protein Concentration through Absorption Spectrophotometry
Measuring Protein Concentration through Absorption Spectrophotometry In this lab exercise you will learn how to homogenize a tissue to extract the protein, and then how to use a protein assay reagent to
More informationLaboratory 5: Properties of Enzymes
Laboratory 5: Properties of Enzymes Technical Objectives 1. Accurately measure and transfer solutions with pipettes 2. Use a Spectrophotometer to study enzyme action. 3. Properly graph a set of data. Knowledge
More informationDetermination of the Mass Percentage of Copper in a Penny. Introduction
Determination of the Mass Percentage of Copper in a Penny Introduction This experiment will cost you one penny ($0.01). The penny must be minted after 1983. Any penny will do; for best results the penny
More informationSome generalization of Langmuir adsorption isotherm
Internet Journal of Chemistry, 2000, 3, 14 [ISSN: 1099-8292]. Article 14 Some generalization of Langmuir adsorption isotherm Leszek Czepirski, Mieczyslaw R. Balys, Ewa Komorowska-Czepirska University of
More informationExperiment 13H THE REACTION OF RED FOOD COLOR WITH BLEACH 1
Experiment 13H FV 1/25/2011(2-run) THE REACTION OF RED FOOD COLOR WITH BLEACH 1 PROBLEM: Determine the rate law for the chemical reaction between FD&C Red Dye #3 and sodium hypochlorite. LEARNING OBJECTIVES:
More informationSurface Area and Porosity
Surface Area and Porosity 1 Background Techniques Surface area Outline Total - physical adsorption External Porosity meso micro 2 Length 1 Å 1 nm 1 µm 1 1 1 1 1 mm macro meso micro metal crystallite 1-1
More informationGRANULAR ACTIVATED CARBON FOR WATER & WASTEWATER TREATMENT
GRANULAR ACTIVATED CARBON FOR WATER & WASTEWATER TREATMENT CARBTROL Corporation September 1992 Rev. 10/92 TP-3 INTRODUCTION Carbon has been used as an adsorbent for centuries. Early uses of carbon were
More informationAustin Peay State University Department of Chemistry Chem 1111. The Use of the Spectrophotometer and Beer's Law
Purpose To become familiar with using a spectrophotometer and gain an understanding of Beer s law and it s relationship to solution concentration. Introduction Scientists use many methods to determine
More informationQuantifying Bacterial Concentration using a Calibrated Growth Curve
BTEC 4200 Lab 2. Quantifying Bacterial Concentration using a Calibrated Growth Curve Background and References Bacterial concentration can be measured by several methods, all of which you have studied
More informationColorimetric Determination of Iron in Vitamin Tablets
Cautions: 6 M hydrochloric acid is corrosive. Purpose: To colorimetrically determine the mass of iron present in commercial vitamin tablets using a prepared calibration curve. Introduction: Iron is considered
More informationKINETIC DETERMINATION OF SELENIUM BY VISIBLE SPECTROSCOPY (VERSION 1.8)
Selenium Determination, Page 1 KINETIC DETERMINATION OF SELENIUM BY VISIBLE SPECTROSCOPY I. BACKGROUND. (VERSION 1.8) The majority of reactions used in analytical chemistry possess the following characteristics:
More informationA 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 informationATOMIC ABSORTION SPECTROSCOPY: rev. 4/2011 ANALYSIS OF COPPER IN FOOD AND VITAMINS
1 ATOMIC ABSORTION SPECTROSCOPY: rev. 4/2011 ANALYSIS OF COPPER IN FOOD AND VITAMINS Buck Scientific Atomic Absorption Spectrophotometer, Model 200 Atomic absorption spectroscopy (AAS) has for many years
More informationElement of same atomic number, but different atomic mass o Example: Hydrogen
Atomic mass: p + = protons; e - = electrons; n 0 = neutrons p + + n 0 = atomic mass o For carbon-12, 6p + + 6n 0 = atomic mass of 12.0 o For chlorine-35, 17p + + 18n 0 = atomic mass of 35.0 atomic mass
More informationThe Determination of an Equilibrium Constant
The Determination of an Equilibrium Constant Computer 10 Chemical reactions occur to reach a state of equilibrium. The equilibrium state can be characterized by quantitatively defining its equilibrium
More information= 1.038 atm. 760 mm Hg. = 0.989 atm. d. 767 torr = 767 mm Hg. = 1.01 atm
Chapter 13 Gases 1. Solids and liquids have essentially fixed volumes and are not able to be compressed easily. Gases have volumes that depend on their conditions, and can be compressed or expanded by
More informationLIQUID CHROMATOGRAPHY HOW MUCH ASPIRIN, ACETAMINOPHEN, AND CAFFEINE ARE IN YOUR PAIN RELIEVER? USING HPLC TO QUANTITATE SUBSTANCES (Revised: 1-13-93)
INTRODUCTION HOW MUCH ASPIRIN, ACETAMINOPHEN, AND CAFFEINE ARE IN YOUR PAIN RELIEVER? USING HPLC TO QUANTITATE SUBSTANCES (Revised: 1-13-93) Headache, sore muscles, arthritis pain... How do you spell relief?
More informationAbsorbance Spectrophotometry: Analysis of FD&C Red Food Dye #40
Absorbance Spectrophotometry: Analysis of FD&C Red Food Dye #40 Note: there is a second document that goes with this one! 2046 - Absorbance Spectrophotometry - Calibration Curve Procedure. The second document
More informationAdsorption at Surfaces
Adsorption at Surfaces Adsorption is the accumulation of particles (adsorbate) at a surface (adsorbent or substrate). The reverse process is called desorption. fractional surface coverage: θ = Number of
More informationWarm-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 informationMolar Mass of Butane
Cautions Butane is toxic and flammable. No OPEN Flames should be used in this experiment. Purpose The purpose of this experiment is to determine the molar mass of butane using Dalton s Law of Partial Pressures
More information5. 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 informationk 2f, k 2r C 2 H 5 + H C 2 H 6
hemical Engineering HE 33 F pplied Reaction Kinetics Fall 04 Problem Set 4 Solution Problem. The following elementary steps are proposed for a gas phase reaction: Elementary Steps Rate constants H H f,
More informationTable of Content. Enzymes and Their Functions Teacher Version 1
Enzymes and Their Functions Jeisa Pelet, Cornell University Carolyn Wilczynski, Binghamton High School Cornell Learning Initiative in Medicine and Bioengineering (CLIMB) Table of Content Title Page Abstract..
More informationLab #11: Determination of a Chemical Equilibrium Constant
Lab #11: Determination of a Chemical Equilibrium Constant Objectives: 1. Determine the equilibrium constant of the formation of the thiocyanatoiron (III) ions. 2. Understand the application of using a
More informationTo determine the mass of iron in one adult dose of either a ferrous sulfate or. ferrous gluconate iron supplement using a colorimetric technique.
Lab: Colorimetric Analysis of Iron in Iron Supplements Purpose To determine the mass of iron in one adult dose of either a ferrous sulfate or ferrous gluconate iron supplement using a colorimetric technique.
More informationPhenolphthalein-NaOH Kinetics
Phenolphthalein-NaOH Kinetics Phenolphthalein is one of the most common acid-base indicators used to determine the end point in acid-base titrations. It is also the active ingredient in some laxatives.
More informationChemistry B11 Chapter 4 Chemical reactions
Chemistry B11 Chapter 4 Chemical reactions Chemical reactions are classified into five groups: A + B AB Synthesis reactions (Combination) H + O H O AB A + B Decomposition reactions (Analysis) NaCl Na +Cl
More informationEnzymes: Amylase Activity in Starch-degrading Soil Isolates
Enzymes: Amylase Activity in Starch-degrading Soil Isolates Introduction This week you will continue our theme of industrial microbiologist by characterizing the enzyme activity we selected for (starch
More informationSpectrophotometry Practical Lesson on Medical Chemistry and Biochemistry
Spectrophotometry Practical Lesson on Medical Chemistry and Biochemistry General Medicine Jiřina Crkovská (translated by Jan Pláteník) 2010/2011 1 Spectrophotometry is one of the most widely used instrumental
More informationHonors Chemistry: Unit 6 Test Stoichiometry PRACTICE TEST ANSWER KEY Page 1. A chemical equation. (C-4.4)
Honors Chemistry: Unit 6 Test Stoichiometry PRACTICE TEST ANSWER KEY Page 1 1. 2. 3. 4. 5. 6. Question What is a symbolic representation of a chemical reaction? What 3 things (values) is a mole of a chemical
More informationph: 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 informationThe literature pertaining to the sorption of gases by solids is now so vast that it is
13 Chapter 2 Physical Adsorption The literature pertaining to the sorption of gases by solids is now so vast that it is impossible for any, except those who are specialists in the experimental technique,
More informationUnderstanding Analytical Chemistry (Weighing, Mixing, Measuring and Evaluating)
Name: Date: Understanding Analytical Chemistry (Weighing, Mixing, Measuring and Evaluating) High School Environmental Science AP Module 1 Environmental Lab NGSSS Big Ideas: This module is a laboratory-based
More informationCalculation of Molar Masses. Molar Mass. Solutions. Solutions
Molar Mass Molar mass = Mass in grams of one mole of any element, numerically equal to its atomic weight Molar mass of molecules can be determined from the chemical formula and molar masses of elements
More informationReaction Stoichiometry and the Formation of a Metal Ion Complex
Reaction Stoichiometry and the Formation of a Metal Ion Complex Objectives The objectives of this laboratory are as follows: To use the method of continuous variation to determine the reaction stoichiometry
More informationThe Mole Concept. The Mole. Masses of molecules
The Mole Concept Ron Robertson r2 c:\files\courses\1110-20\2010 final slides for web\mole concept.docx The Mole The mole is a unit of measurement equal to 6.022 x 10 23 things (to 4 sf) just like there
More informationEXPERIMENT 5. Molecular Absorption Spectroscopy: Determination of Iron With 1,10-Phenanthroline
EXPERIMENT 5 Molecular Absorption Spectroscopy: Determination of Iron With 1,10-Phenanthroline UNKNOWN Submit a clean, labeled 100-mL volumetric flask to the instructor so that your unknown iron solution
More informationChem 131A: Absorbance of Riboflavin
Chem 131A: Absorbance of Riboflavin Purpose: The purpose of this experiment is to: 1) Familiarize the student with the use of the HP 8452 diode array spectrophotometer, 2) examine the limitations of the
More informationExperiment 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 informationGeneral Chemistry I (FC, 09-10) Lab #3: The Empirical Formula of a Compound. Introduction
General Chemistry I (FC, 09-10) 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, does not
More informationSORPTION ISOTHERM STUDY ON TWO POLYAMIDE NANOFIBEROUS MEMBRANES. Yan WANG, Jakub WIENER, Guocheng ZHU
SORPTION ISOTHERM STUDY ON TWO POLYAMIDE NANOFIBEROUS MEMBRANES Yan WANG, Jakub WIENER, Guocheng ZHU Technical University of Liberec, Faculty of Textile Engineering, Department of Textile Materials, Liberec,
More informationCHEMISTRY STANDARDS BASED RUBRIC ATOMIC STRUCTURE AND BONDING
CHEMISTRY STANDARDS BASED RUBRIC ATOMIC STRUCTURE AND BONDING Essential Standard: STUDENTS WILL UNDERSTAND THAT THE PROPERTIES OF MATTER AND THEIR INTERACTIONS ARE A CONSEQUENCE OF THE STRUCTURE OF MATTER,
More information4.2 Bias, Standards and Standardization
4.2 Bias, Standards and Standardization bias and accuracy, estimation of bias origin of bias and the uncertainty in reference values quantifying by mass, chemical reactions, and physical methods standard
More informationReview - 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 informationWe will try to get familiar with a heat pump, and try to determine its performance coefficient under different circumstances.
C4. Heat Pump I. OBJECTIVE OF THE EXPERIMENT We will try to get familiar with a heat pump, and try to determine its performance coefficient under different circumstances. II. INTRODUCTION II.1. Thermodynamic
More information2 Spectrophotometry and the Analysis of Riboflavin
2 Spectrophotometry and the Analysis of Riboflavin Objectives: A) To become familiar with operating the Platereader; B) to learn how to use the Platereader in determining the absorption spectrum of a compound
More informationKINETIC THEORY AND THERMODYNAMICS
KINETIC THEORY AND THERMODYNAMICS 1. Basic ideas Kinetic theory based on experiments, which proved that a) matter contains particles and quite a lot of space between them b) these particles always move
More informationActivity Sheets Enzymes and Their Functions
Name: Date: Activity Sheets Enzymes and Their Functions amylase What are Enzymes? starch glucose Enzymes are compounds that assist chemical reactions by increasing the rate at which they occur. For example,
More informationACID-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 informationReaction Rates and Chemical Kinetics. Factors Affecting Reaction Rate [O 2. CHAPTER 13 Page 1
CHAPTER 13 Page 1 Reaction Rates and Chemical Kinetics Several factors affect the rate at which a reaction occurs. Some reactions are instantaneous while others are extremely slow. Whether a commercial
More informationStates of Matter CHAPTER 10 REVIEW SECTION 1. Name Date Class. Answer the following questions in the space provided.
CHAPTER 10 REVIEW States of Matter SECTION 1 SHORT ANSWER Answer the following questions in the space provided. 1. Identify whether the descriptions below describe an ideal gas or a real gas. ideal gas
More information9. Analysis of an Acid-Base Titration Curve: The Gran Plot
9. Analysis of an Acid-Base Titration Curve: The Gran Plot In this experiment, you will titrate a sample of pure potassium hydrogen phthalate (Table 10-4) with standard NaOH. A Gran plot will be used to
More informationTHE ACTIVITY OF LACTASE
THE ACTIVITY OF LACTASE Lab VIS-8 From Juniata College Science in Motion Enzymes are protein molecules which act to catalyze the chemical reactions in living things. These chemical reactions make up the
More informationName Class Date. In the space provided, write the letter of the term or phrase that best completes each statement or best answers each question.
Assessment Chapter Test A Chapter: States of Matter In the space provided, write the letter of the term or phrase that best completes each statement or best answers each question. 1. The kinetic-molecular
More informationFactors Affecting Enzyme Activity
INTRODUCTION Factors Affecting Enzyme Activity The chemical reactions occurring in living things are controlled by enzymes. An enzyme is a protein in the cell which lowers the activation energy of a catalyzed
More informationThe 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 information3.4 TEST FOR BACTERIAL ENDOTOXINS. Final text for revision of The International Pharmacopoeia
Document QAS/11.5 FINAL July 01 3. TEST FOR BACTERIAL ENDOTOXINS Final text for revision of The International Pharmacopoeia This monograph was adopted at the Forty-sixth WHO Expert Committee on Specifications
More informationUnit 2: Quantities in Chemistry
Mass, Moles, & Molar Mass Relative quantities of isotopes in a natural occurring element (%) E.g. Carbon has 2 isotopes C-12 and C-13. Of Carbon s two isotopes, there is 98.9% C-12 and 11.1% C-13. Find
More informationUpon completion of this lab, the student will be able to:
1 Learning Outcomes EXPERIMENT B4: CHEMICAL EQUILIBRIUM Upon completion of this lab, the student will be able to: 1) Analyze the absorbance spectrum of a sample. 2) Calculate the equilibrium constant for
More informationThe Molar Mass of a Gas
The Molar Mass of a Gas Goals The purpose of this experiment is to determine the number of grams per mole of a gas by measuring the pressure, volume, temperature, and mass of a sample. Terms to Know Molar
More informationChemistry. The student will be able to identify and apply basic safety procedures and identify basic equipment.
Chemistry UNIT I: Introduction to Chemistry The student will be able to describe what chemistry is and its scope. a. Define chemistry. b. Explain that chemistry overlaps many other areas of science. The
More information105 Adopted: 27.07.95
105 Adopted: 27.07.95 OECD GUIDELINE FOR THE TESTING OF CHEMICALS Adopted by the Council on 27 th July 1995 Water Solubility INTRODUCTION 1. This guideline is a revised version of the original Guideline
More informationDETERMINING THE ENTHALPY OF FORMATION OF CaCO 3
DETERMINING THE ENTHALPY OF FORMATION OF CaCO 3 Standard Enthalpy Change Standard Enthalpy Change for a reaction, symbolized as H 0 298, is defined as The enthalpy change when the molar quantities of reactants
More informationChapter 4. Chemical Composition. Chapter 4 Topics H 2 S. 4.1 Mole Quantities. The Mole Scale. Molar Mass The Mass of 1 Mole
Chapter 4 Chemical Composition Chapter 4 Topics 1. Mole Quantities 2. Moles, Masses, and Particles 3. Determining Empirical Formulas 4. Chemical Composition of Solutions Copyright The McGraw-Hill Companies,
More informationChemistry 2351: Inorganic Chemistry I Laboratory Manual
Spectroscopic Determination of a Complex Ion's Stoichiometry by Job's Method ABSTRACT This experiment is adapted from Angelici's classic experiment, but uses Fe(H 2 O) 6-n (SCN) n 3-n as the complex ion.
More informationApparatus 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 informationChemistry 13: States of Matter
Chemistry 13: States of Matter Name: Period: Date: Chemistry Content Standard: Gases and Their Properties The kinetic molecular theory describes the motion of atoms and molecules and explains the properties
More informationChemical Reactions Practice Test
Chemical Reactions Practice Test Chapter 2 Name Date Hour _ Multiple Choice Identify the choice that best completes the statement or answers the question. 1. The only sure evidence for a chemical reaction
More information7-5.5. Translate chemical symbols and the chemical formulas of common substances to show the component parts of the substances including:
7-5.5 Translate chemical symbols and the chemical formulas of common substances to show the component parts of the substances including: NaCl [salt], H 2 O [water], C 6 H 12 O 6 [simple sugar], O 2 [oxygen
More informationThermodynamics of Mixing
Thermodynamics of Mixing Dependence of Gibbs energy on mixture composition is G = n A µ A + n B µ B and at constant T and p, systems tend towards a lower Gibbs energy The simplest example of mixing: What
More informationCalculations with Chemical Formulas and Equations
Chapter 3 Calculations with Chemical Formulas and Equations Concept Check 3.1 You have 1.5 moles of tricycles. a. How many moles of seats do you have? b. How many moles of tires do you have? c. How could
More informationIB Chemistry. DP Chemistry Review
DP Chemistry Review Topic 1: Quantitative chemistry 1.1 The mole concept and Avogadro s constant Assessment statement Apply the mole concept to substances. Determine the number of particles and the amount
More informationThe Mole Notes. There are many ways to or measure things. In Chemistry we also have special ways to count and measure things, one of which is the.
The Mole Notes I. Introduction There are many ways to or measure things. In Chemistry we also have special ways to count and measure things, one of which is the. A. The Mole (mol) Recall that atoms of
More informationExp 13 Volumetric Analysis: Acid-Base titration
Exp 13 Volumetric Analysis: Acid-Base titration Exp. 13 video (time: 47:17 minutes) Titration - is the measurement of the volume of a standard solution required to completely react with a measured volume
More informationChemical Changes. Measuring a Chemical Reaction. Name(s)
Chemical Changes Name(s) In the particle model of matter, individual atoms can be bound tightly to other atoms to form molecules. For example, water molecules are made up of two hydrogen atoms bound to
More informationStandard Test Methods for Carbon Black Surface Area by Multipoint B.E.T. Nitrogen Adsorption 1
Designation: D 4820 99 Standard Test Methods for Carbon Black Surface Area by Multipoint B.E.T. Nitrogen Adsorption 1 This standard is issued under the fixed designation D 4820; the number immediately
More information