# COLORIMETER. Description 0358BT. Figure 1. The Colorimeter

Save this PDF as:

Size: px
Start display at page:

## Transcription

1 COLORIMETER Description 0358BT Figure 1. The Colorimeter

2 Introduction The Colorimeter is designed to determine the concentration of a solution by analyzing its color intensity. Monochromatic light from a LED light source passes through a cuvette containing a solution sample, as shown in figure 2. Some of the incoming light is absorbed by the solution. As a result, light of a lower intensity strikes a photodiode. The Colorimeter consists of LEDs for red (635 nm), for green (565 nm) and for blue (470 nm) light. Figure 2. Colorimeter The Colorimeter is delivered with a BT plug and can be connected to the following interfaces: UIA/UIB boards through the Measuring Console (via 0520 adapter) CoachLab CoachLab II Texas Instruments CBL data logger. There is an adapter (art. 0520) to connect sensors with BT-plugs to 4-mm inputs. Transmittance and absorbance The amount of light that penetrates a solution is known as transmittance. Transmittance T can be expressed as the ration of the intensity of the transmitted light I t, and the initial intensity of the light beam I 0 as expressed by the formula: T = It / I 0 The transmittance of the sample is determined by the cell or cuvette width (d) and the concentration of the solution (c). The relation between T, d, c is: T d c = e α (α is an constant that depends on the solution and used the light wavelength) From the two previous equations, the expression for absorbance is obtained: A = log( T ) = log(1/ T ) = log( e) α d c = ε d c (ε is the molar absorptivity of the solution) For a given solution contained in a cuvette with a constant cell width, the Absorbance is proportional to the concentration: 2

3 A = κ c (this is Beer's law) In many chemical and biological experiments this law is assumed for making calibration line for determining concentration. Absorbance and Transimittance ranges for the colorimeter For best results our laboratory testing of the colorimeter indicates that absorbance or transmittance values should fall with these ranges: Transmittance(T) Absorbance (A) Next to the limitations of the transmittance range of the colorimeter there is a measurement error in the concentration (absorbance) measurement, which strongly depends on the error in the transmittance (dt% in figure 3). To get sufficiently reliable results calibration solutions should be used which lie in the flat part of the curve dt% = 1% (i.e. 1% accuracy of the transmission). Figure 3. The measurement error in percent in the concentration (or absorbance) as function of the transmission for different accuracy's (dt%) of the transmittance range. 3

4 Determining of the wavelength You can select three LED light colors: the red (635 nm), the green (565 nm) or the blue (470 nm). There are several ways you can decide which of three wavelengths to use: Method 1. Look at the color of the solution. Remember that the color of solution is the color of light which passes through it. You probably want to use a different color of light that will be absorbed, rather than transmitted. For example: with a blue CuSO 4 solution, use the red LED (635 nm). Method 2. Place a cuvette containing the solution in the colorimeter. And check to see which of three wavelengths yields the highest absorbance (low transmittance). Method 3. Directions for most colorimetry experiments express a recommended wavelength. Use the closest of the three wavelengths on the colorimeter. Even if the LED wavelength is somewhat different, a Beer's law curve can usually be obtained at almost any wavelength in the vicinity of the recommended wavelength. Calibration of the colorimeter Method 1. A voltage-concentration calibration The general method for doing a 2-point calibration with the Colorimeter is similar to that used for most other colorimeters or spectrophotometers. A 0% calibration is done with no light passing through cuvette. The wavelength knob on the colorimeter is turned to '0% T'. The lid of cuvette slot must be closed. In this position computer can read data from the Colorimeter. But the light source is turned off. Since the light is off it makes no difference if a cuvette is in the cuvette slot. A 100% calibration is done with the wavelength knob turned to select one of the three LED wavelengths. This turns on the red, green, or blue LED. A blank is placed in the cuvette slot and the lid of the colorimeter is closed. The blank is a cuvette containing the solvent used on the solution being studied, usually distilled water. The blank acts as a control by taking into account the small amount of light absorbed by the solvent and by the walls of the cuvette. 4

5 To get more points calibration the number of known sample solutions can be used. Methode 2. Using the Absorbance calibration of the Colorimeter For the voltage-absorbance calibrations (for the three wavelengths) which are placed in the Coach 5 library, the Colorimeter works like an Absorbance-meter (water as a solvent). The calibrated signal is proportional to the concentration. The proportion constant that has to be used to calculate the concentration is not taken into account because it depends on the substance that is used in the experiment. The proportion constant between absorbance and concentration can be found by making a calibration line on paper or with help of Coach 5. Sometimes a concentration-absorbance calibration is not necessary, for example in the investigating of a (pseudo) first-order reaction. In this type of mechanism the rate of reaction (v) is: v = dc/dt = k.*c According to the Beer's law a concentration and absorbance are proportional: A = ê*c so c = (1/ê) * A Combining the two equations the following expression is obtained: v = d[(1/ê)*a)]/dt = k.(1/ê)*a so da/dt = k*a By the measurement of the absorbance the rate of reaction (k) can be determined. Using cuvettes The Colorimeter is designed to use polystyrene 1cm x 1cm cuvettes (standard disposable cuvettes). Two opposite sides of the cuvette are ribbed and are not intended to transmit light from the LED. The two smooth surfaces are intended to transmit lights. It is important to position the cuvette correctly in the colorimeter. We recommended this be done as shown in Figure 4, with the ribbed edges facing away from and toward you, and the smooth edges facing left to right. The light travels from left to right from the LED through the cuvette to the photodiode. It should be also noted that there is often a small variation in the amount of light absorbed by the cuvette if it is rotated 180 between trials. To avoid this, you should use a water -proof marker to make a reference mark on the right side of the top of the cuvette as shown in Figure 4. Remind students to align this reference mark with the white mark on the top right side of the colorimeter each time they insert a cuvette. 5

6 Figure 4. Placing a cuvette in the colorimeter Plastic cuvettes vary slightly in the amount of light they absorb. You may ignore these differences. For most experiments thus variation will not have a noticeable effect on experimental results. For best results, variation in light absorbed by individual cuvettes can be controlled either by using the same cuvette for all trials of a particular experiment or by matching a set of cuvettes. The easiest and the most reliable is the first method. The cuvette has to be cleaned and dry after each trial or rinsed several times with the solution that will be added to it. As an alternative you may choose to match cuvettes. Matched cuvettes are a set of cuvettes that all absorb light (when empty) at approximately the same level. To match a set of cuvettes use clean, dry cuvettes, put a reference mark on one of the clear sides of the cuvettes so it is always oriented the same way in the cuvette slot. Place each cuvette in the batch of the Colorimeter and record transmittance values for each. When you are finished, group cuvettes according to the similar %T values. Each of these groups represents a set of matched cuvettes. The total volume of a cuvette is 4.1 ml. Fill the cuvette for every measurement with 2.2 to 3.5 ml. As a reminder to students mark the level with a water-proof marker on one of the ribbed sides of each cuvette. Suggestions for experiments Beer's law Crystal violet Dilute solutions of crystal violet yield a good Beer's law curve using the green LED (565 nm). A stock solution 8 x 10-5 M crystal violet is prepared by adding 65.3 mg of solid crystal violet to enough water to yields 2 liters of solution. 6

7 Copper sulfate Standard solutions that are 0.1 M, 0.2 M, 0.3 M and 0.4 M CuSO 4 will yield a good Beer's law curve at 635 nm (red LED). Or prepare a stock solution by adding 10 g of NH 4 NO 3 to 10 ml 0.1 M CuSO 4 and 90 ml 0,2 M NH 3 (forms Cu(NH 3 ) 4 2+ complex ion) and dilute to obtain standard solutions. Determination of the rate law for the reaction of crystal violet Add 10 ml of 8 x 10-5 M crystal violet solution to 5.0 ml of 0.10 M NaOH and fill with water to 100 ml. The de-coloring of the solution takes from 15 to 20 minutes. Figure 5. Measurement of the transmission during the reaction from crystal violet to sodium hydroxide. 10 ml (0.1mM) of crystal violet solution is mixed with 10 ml sodium hydroxide (0. M) in a glass and the measurement is started. Circa 3 ml of new solution is added to cuvette and the cuvette is placed in the colorimeter. During the measurement values of ln(e) are calculated. 7

8 The name of the Colorimeter in the sensor library of Coach 5 program is Colorimeter 470 nm (0358&bt) (CMA) Colorimeter 565 nm (0358&bt) (CMA) Colorimeter 635 nm (0358&bt) (CMA). Technical data For the best results the absorbance and transmittance should fall within: Percent transmittance: 28% - 90% Absorbance Wavelengths ranges Blue (470 nm or 4700 Å) Green (565 nm or 5650 Å) Red (635 nm or 6350 Å) Supplied with 15 cuvettes Connection BT (British Telecom) plug CENTRE FOR MICROCOMPUTER APPLICATIONS Kruislaan 404, 1098 SM Amsterdam, The Netherlands Fax: , 8

### EXPERIMENT 7B FORMATION OF A COMPLEX ION

EXPERIMENT 7B FORMATION OF A COMPLEX ION INTRODUCTION: The purpose of this experiment is to measure the formation constant of the tetraamminecopper(ii) ion by colorimetry. Anhydrous copper sulfate (CuSO

### VISIBLE SPECTROSCOPY

VISIBLE SPECTROSCOPY Visible spectroscopy is the study of the interaction of radiation from the visible part (λ = 380-720 nm) of the electromagnetic spectrum with a chemical species. Quantifying the interaction

### Energy (J) -8E-19 -1.2E-18 -1.6E-18 -2E-18

Spectrophotometry Reading assignment:. http://en.wikipedia.org/wiki/beer-lambert_law Goals We will study the spectral properties of a transition metal-containing compound. We will also study the relationship

### CONDUCTIVITY SENSOR. Description D0382. Figure 1. The Conductivity Sensor

CONDUCTIVITY SENSOR Description D0382 Figure 1. The Conductivity Sensor Short Description The Conductivity Sensor can be used to measure either solution conductivity or total ion concentration of aqueous

### Phenolphthalein-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.

### EXPERIMENT 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

### The 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

### Using the Spectrophotometer

Using the Spectrophotometer Introduction In this exercise, you will learn the basic principals of spectrophotometry and and serial dilution and their practical application. You will need these skills to

### Austin 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

### Experiment 1 (Lab period 1) Spectrophotometry: Absorption spectra and the use of light absorption to measure concentration

Experiment 1 (Lab period 1) Spectrophotometry: Absorption spectra and the use of light absorption to measure concentration Spectrophotometry is a procedure that is frequently utilized in biological laboratories.

### Using a Spectrophotometer

Introduction: Spectrophotometry Using a Spectrophotometer Many kinds of molecules interact with or absorb specific types of radiant energy in a predictable fashion. For example, when while light illuminates

### The Determination of the Percent of Salicylic Acid in Aspirin

Salicylic acid The Determination of the Percent of Salicylic Acid in Aspirin Aspirin or acetylsalicylic acid, may be prepared by the reaction of salicylic acid and either acetic acid or acetic anhydride

### Beer's Law: Colorimetry of Copper(II) Solutions

Exercise 11 Page 1 Illinois Central College CHEMISTRY 130 Name: Beer's Law: Colorimetry of Copper(II) Solutions Objectives In this experiment, we will use Beer's Law to determine the unknown concentrations

### Evaluation copy. Biological Membranes. Computer

Biological Membranes Computer 9 The primary objective of this experiment is to determine the stress that various factors, such as osmotic balance, detergents, and ph, have on biological membranes. Membranes

### Beer-Lambert Law: Measuring Percent Transmittance of Solutions at Different Concentrations (Teacher s Guide)

Beer-Lambert Law: Measuring Percent Transmittance of Solutions at Different Concentrations (Teacher s Guide) OVERVIEW Students will study the relationship between transmittance, absorbance, and concentration

### Experiment 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

### Upon 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

### Solubility Product Constants

Solubility Product Constants PURPOSE To measure the solubility product constant (K sp ) of copper (II) iodate, Cu(IO 3 ) 2. GOALS 1 To measure the molar solubility of a sparingly soluble salt in water.

### CHM 161 Spectrophotometry: Analysis of Iron(II) in an Aqueous Solution

CHM 161 Spectrophotometry: Analysis of Iron(II) in an Aqueous Solution Introduction Many compounds exhibit colors in aqueous solution due to the absorption of certain wavelengths of light. The intensity

### SPECTROPHOTOMETRY. Blue. Orange

Appendix I FV /26/5 SPECTROPHOTOMETRY Spectrophotometry is an analytical technique used to measure the amount of light of a particular wavelength absorbed by a sample in solution. This measurement is then

### Reaction 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

### Molecular Biology of Life Laboratory BIOL 123. Spectrophotometer

Spectrophotometer A spectrophotometer is an instrument that measures the amount of light that can pass through a solution. It is apparent that less light is allowed to pass through a highly turbid or colored

### EXPERIMENT 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

### Evaluation copy. Case File 9. A Killer Cup of Coffee? GlobalTech manager dies

Case File 9 Killer Cup of Coffee: Using colorimetry to determine concentration of a poison Determine the concentration of cyanide in the solution. A Killer Cup of Coffee? SOUTH PAINTER, Tuesday: It was

### 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,

### Spectrophotometer measurement laboratory practice

Spectrophotometer measurement laboratory practice The operating principle of a Spectrophotometer is based on dispersion of light (Fig.1.) Fig 1. Dispersion of light A spectrophotometer is an instrument

### Experiment 3 Measurement of an Equilibrium Constant

3-1 Experiment 3 Measurement of an Equilibrium Constant Introduction: Most chemical reactions (e.g., the generic A + B 2C) are reversible, meaning they have a forward reaction (A + B forming 2C) and a

### Coordination Compounds with Copper (II) Prelab (Week 2)

Coordination Compounds with Copper (II) Prelab (Week 2) Name Total /10 SHOW ALL WORK NO WORK = NO CREDIT 1. What is the purpose of this experiment? 2. Write the generic chemical formula for the coordination

### Determining the Free Chlorine Content of Swimming Pool Water. HOCl H + + OCl. Evaluation copy

Determining the Free Chlorine Content of Swimming Pool Water Computer 33 Physicians in the nineteenth century used chlorine water as a disinfectant. Upon the discovery that certain diseases were transmitted

### Experiment 6: Determination of the Equilibrium Constant for Iron Thiocyanate Complex

Experiment 6: Determination of the Equilibrium Constant for Iron Thiocyanate Complex The data for this lab will be taken as a class to get one data set for the entire class. I. Introduction A. The Spectrophotometer

### LAB. THE SPECTROPHOTOMETER

Name AP Biology Period Date LAB. THE SPECTROPHOTOMETER INTRODUCTION: A spectrophotometer is a valuable instrument in biology. It allows us to measure and compare the concentration of materials in solution

### Chemistry 111 Lab: Intro to Spectrophotometry Page E-1

Chemistry 111 Lab: Intro to Spectrophotometry Page E-1 SPECTROPHOTOMETRY Absorption Measurements & their Application to Quantitative Analysis study of the interaction of light (or other electromagnetic

### Lab 5: Quantitative Analysis- Phosphates in Water By: A Generous Student. LBS 171L Section 9 TA: Dana October 27, 2005

How uch Phosphate is the Body Being Exposed to During a Lifetime by Showering? Lab 5: Quantitative Analysis- Phosphates in Water By: A Generous Student LBS 171L Section 9 TA: Dana October 7, 005 [Note:

### Experiment #5: Qualitative Absorption Spectroscopy

Experiment #5: Qualitative Absorption Spectroscopy One of the most important areas in the field of analytical chemistry is that of spectroscopy. In general terms, spectroscopy deals with the interactions

### THE IRON(III) THIOCYANATE REACTION SYSTEM

Experiment 7 THE IRON(III) THIOCYANATE REACTION SYSTEM Prepared by Ross S. Nord, Chemistry Department, Eastern Michigan University PURPOSE To investigate a novel reaction system by utilizing a spectrophotometer.

### 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

### Chem 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

### INTRODUCTION TO SPECTROPHOTOMETRY Analysis of Dye Mixtures

Chemistry 135 For this experiment: INTRODUCTION TO SPECTROPHOTOMETRY Analysis of Dye Mixtures Complete the Prelab and obtain a stamp before you begin the experiment. Clark College Write your notebook prelab

### 2 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

### Absorbance 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

### Experiment 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:

### Determining the Percent Composition of a Copper Chloride Hydrate

Determining the Percent Composition of a Copper Chloride Hydrate Overview: The mass percents of Cu, Cl and H 2 O in a compound are determined by separating and massing the three components. The resulting

### AP Chemistry Laboratory #16: Determination of the Equilibrium Constant of FeSCN 2+

AP Chemistry Laboratory #16: Determination of the Equilibrium Constant of FeSCN 2 Lab day: Wednesday, February 12, 2014 Lab due: Wednesday, February 19, 2014 Goal (list in your lab book): The goal of this

### The Determination of an Equilibrium Constant

The Determination of an Equilibrium Constant Chemical reactions occur to reach a state of equilibrium. The equilibrium state can be characterized by quantitatively defining its equilibrium constant, K

### Kinetics mg of p-nitrophenyl acetate, 65 ml of methanol, 13.9 mg of p-nitrophenol, 6.7 g of KCl.

Kinetics In this experiment you will determine the order of a reaction with respect to the two reactants, p-nitrophenyl acetate and hydroxide. You will also determine the rate constant for this reaction.

### Evaluation copy. Macromolecules: Experiments with Protein. Computer 17

Macromolecules: Experiments with Protein Computer 17 This exercised is designed to introduce you to the study of macromolecules. Proteins, DNA, RNA, and polysaccharides such as starch, glycogen, and cellulose

### Cadmium Reduction Method Method 8039 0.3 to 30.0 mg/l NO 3 N (HR) Powder Pillows or AccuVac Ampuls

Nitrate DOC316.53.01066 Cadmium Reduction Method Method 8039 0.3 to 30.0 mg/l NO 3 N (HR) Powder Pillows or AccuVac Ampuls Scope and application: For water, wastewater and seawater. Test preparation Instrument-specific

### Determining An Equilibrium Constant Using Spectrophotometry and Beer s Law

Objectives: Determining An Equilibrium Constant Using Spectrophotometry and Beer s Law 1.) To determine the equilibrium constant for the reaction of iron (III) and thiocyanate to form the thiocyanatoiron(iii)

### Experiment: TITRATION OF AN ACID WITH A BASE

Experiment: TITRATION OF AN ACID WITH A BASE INTRODUCTION: The word titration is derived from a French word, "titre" which means "to bestow a title upon or to standardize". The purpose of a chemical titration

### Lab 2 Biochemistry. Learning Objectives. Introduction. Lipid Structure and Role in Food. The lab has the following learning objectives.

1 Lab 2 Biochemistry Learning Objectives The lab has the following learning objectives. Investigate the role of double bonding in fatty acids, through models. Developing a calibration curve for a Benedict

### Application Note: Absorbance

Units Units Theory of absorbance Light absorption occurs when atoms or molecules take up the energy of a photon of light, thereby reducing the transmission of light as it is passed through a sample. Light

### Phosphates (ortho- and total)

INTRODUCTION Phosphates (ortho- and total) Phosphorus is an essential nutrient for all aquatic plants and algae. Only a very small amount is needed, however, so an excess of phosphorus can easily occur.

### EXPERIMENT 2 Reaction Order

EXPERIMENT 2 Reaction Order Introduction How a reaction progresses over time is an indication of its reaction order. In the rate laws, (Rate = k[a] m [B] n ), found in the first experiment, you calculated

### Chapter 3. Mastering the micropipette. Objectives

Mastering the micropipette Welcome to the microworld! In this class, you are working with microorganisms, including yeast and bacteria, millions of which would fit into a period on this page. You will

### GlobalTech manager dies

Case File 9 Killer Cup of Coffee: Using colorimetry to determine concentration of a poison Determine the concentration of cyanide in the solution. A Killer Cup of Coffee? GlobalTech manager dies SOUTH

### Powder Pillows 0.01 to 1.60 mg/l SiO 2 (colorimeters)

Silica DOC316.53.01132 Heteropoly Blue Method 1 Method 8186 0.010 to 1.600 mg/l SiO 2 (spectrophotometers) Powder Pillows 0.01 to 1.60 mg/l SiO 2 (colorimeters) Scope and application: For boiler and ultrapure

### Schools Analyst Competition

Royal Society of Chemistry Analytical Division North West Region Schools Analyst Competition 28 th March 2006 Experimental Handbook Adran Cemeg - Department of Chemistry Prifysgol Cymru - University of

### Chemistry 118 Laboratory University of Massachusetts Boston Beer s Law

Name: LEARNING GOALS: Chemistry 118 Laboratory University of Massachusetts Boston Beer s Law 1. Become familiar with the concept of concentration and molarity. 2. Become familiar with making dilutions

### Color, True and Apparent

Color, True and Apparent DOC316.53.01037 Platinum-Cobalt Standard Method 1, 2, 3 Method 8025 15 to 500 color units Scope and application: For water, wastewater and seawater; equivalent to NCASI method

### ENZYME KINETICS ENZYME-SUBSTRATE PRODUCTS

ENZYME KINETICS INTRODUCTION The study of reaction rates catalyzed by enzymes and the factors affecting them is generally referred to as enzyme kinetics. The basic components of an enzyme catalyzed reaction

### Determination 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

### Color, True and Apparent

Color, True and Apparent DOC316.53.01037 Platinum-Cobalt Standard Method 1, 2, 3 Method 8025 15 to 500 color units 5 to 500 color units (low range technique) Scope and application: For water, wastewater

### Spectrophotometry 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

### Solution Stoichiometry Quantitative Preparation of Aqueous Solutions

Solution Stoichiometry Quantitative Preparation of Aqueous Solutions Introduction Page 1 of 11 In this week s lab, you and your lab partner will apply your prelab calculations to the preparation of aqueous

### Experiment 2 Determination of the Composition of Iron-Phenanthroline Complex by Job s Method Objective Theory

Experiment 2 Determination of the Composition of Iron-Phenanthroline Complex by Job s Method Objective To establish the formula of a colored complex by the spectrophotometric method Theory The formation

### Kinetics of Crystal Violet Fading AP* Chemistry Big Idea 4, Investigation 11 An Advanced Inquiry Lab

Introduction Kinetics of Crystal Violet Fading AP* Chemistry Big Idea 4, Investigation 11 An Advanced Inquiry Lab Catalog o. AP7644S Publication o. 7644S Crystal violet is a common, beautiful purple dye.

### Expt B: Determining the Equilibrium Constant of Bromothymol Blue. Keywords: Equilibrium Constant, ph, indicator, spectroscopy

Objectives: Keywords: Equilibrium Constant, ph, indicator, spectroscopy Prepare all solutions needed for measurement of the equilibrium constant for bromothymol Make the required spectroscopic measurements

### Info Note UV-VIS Nomenclature and Units

Info Note 804: Ultraviolet-visible spectroscopy or ultraviolet-visible spectrophotometry (UV/VIS) involves the spectroscopy of photons in the UV-visible region. It uses light in the visible and adjacent

### Colorimetric 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

### CHEM 161: Beer s Law and Analysis of a Sports Drink

CHEM 161: Beer s Law and Analysis of a Sports Drink Introduction Although sunlight appears white, it contains a spectrum of colors. A rainbow actually shows this range of colors in visible light: violet,

### Experiment II 1 Chemical Kinetics

CH 142- Experiment III Experiment II 1 Chemical Kinetics Introduction A company that manufacturers dyes has had problems with its newest shade of purple: crystal violet. With the recent 70 s craze, they

### LZV585 (B) The 1-cm path is aligned with the arrow on the adapter. 5940506

Chlorine, Total DOC316.53.01029 USEPA DPD Method 1 Method 10070 0.1 to 10.0 mg/l Cl 2 (HR) Powder Pillows Scope and application: For testing higher levels of total chlorine (free and combined) in drinking

### Dimethylglyoxime Method Method 10220 0.1 to 6.0 mg/l Ni TNTplus 856

Nickel DOC316.53.01065 Dimethylglyoxime Method Method 10220 0.1 to 6.0 mg/l Ni TNTplus 856 Scope and application: For water and wastewater. Test preparation Instrument-specific information Table 1 shows

### USEPA 1 FerroVer Method 2 Method 8008 0.02 to 3.00 mg/l Fe Powder Pillows or AccuVac Ampuls

Iron, Total DOC316.53.01053 USEPA 1 FerroVer Method 2 Method 8008 0.02 to 3.00 mg/l Fe Powder Pillows or AccuVac Ampuls Scope and application: For water, wastewater and seawater; digestion is required

### Spectrophotometric and Potentiometric Determination of ph

Spectrophotometric and Potentiometric Determination of ph Introduction Determination of ph is one of the most frequently performed measurements in chemistry. The potentiometric method with a glass electrode

### FerroVer Method 1 Method 10249 0.1 to 3.0, 1.0 to 30.0 and 10.0 to 300.0 mg/l Fe Powder Pillows

Iron, Total DOC316.53.01314 FerroVer Method 1 Method 10249 0.1 to 3.0, 1.0 to 30.0 and 10.0 to 300.0 mg/l Fe Powder Pillows Scope and application: For oil and gas field waters; digestion is required for

### Lab #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

### Spectrophotometric Determination of the pka of Bromothymol Blue

Spectrophotometric Determination of the pka of Bromothymol Blue INRODUCION cidbase indicators are compounds that are simply weak acids (or bases) that exhibit different colors depending on whether they

### Water Quality 1 - Spectrophotometric Determination of Iron in Drinking Water

Water Quality 1 - Spectrophotometric Determination of Iron in Drinking Water Introduction The safety of drinking water is a very important public health issue. The United States and World Health Organization

### Phosphorus, Reactive (Orthophosphate)

Phosphorus, Reactive (Orthophosphate) DOC316.53.01113 Amino Acid Method 1 Method 8178 0.23 to 30.00 mg/l PO 4 Reagent Solution Scope and application: For water, wastewater and seawater. 1 Adapted from

### Biology 3460 - Plant Physiology - Lab Exercise 2 Basic Lab Techniques

Biol3460 Lab 1 1 Biology 3460 - Plant Physiology - Lab Exercise 2 Basic Lab Techniques Objectives: This lab is intended to: (1) provide an introduction to basic techniques used in biology labs (2) provide

### Colorimeter Sensor for the LogIT Microsense system

Colorimeter Sensor for the LogIT Microsense system Overview The basic principal of colorimetry is to measure the absorbance of a coloured solution to different colours of light shone through it as this

### Chem 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

### Lab 2. Spectrophotometric Measurement of Glucose

Lab 2 Spectrophotometric Measurement of Glucose Objectives 1. Learn how to use a spectrophotometer. 2. Produce a glucose standard curve. 3. Perform a glucose assay. Safety Precautions Glucose Color Reagent

### Table 212 Instrument-specific information. Instrument Sample cell Cell orientation. DR Fill line faces right

, Trak, 8317 DOC316.53.01054 Trak Fast Column Extraction Method Method 8317 5 to 150 µg/l Scope and Application: For drinking water Test preparation How to use instrument-specific information The Instrument-specific

### Problem Set 6 UV-Vis Absorption Spectroscopy. 13-1. Express the following absorbances in terms of percent transmittance:

Problem Set 6 UV-Vis Absorption Spectroscopy 13-1. Express the following absorbances in terms of percent transmittance: a 0.051 b 0.918 c 0.379 d 0.261 e 0.485 f 0.072 A = log P o /P = log1/t = - log T

### ATOMIC 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

### Category 5 points 4 points 3 points 2 points 1 point 0 points Participation Participated fully. Mostly on-task. Safety reminders needed.

Lab Report Rubric Category 5 points 4 points 3 points 2 points 1 point 0 points Participation Participated fully Mostly on-task Minimal and Safety participation Prelab /10 Observations Data Units & Significant

### 1 Spectrophotometric Analysis of Commercial Aspirin

1 Spectrophotometric Analysis of Commercial Aspirin Name: _ Date: Lab Day/Time: Lab Partner: Objectives Learn about the absorption of light by molecules Learn the basic components of a spectrophotometer

### F. ELECTRONIC SPECTRA OF COORDINATION COMPOUNDS

Introduction: F. ELECTRONIC SPECTRA OF COORDINATION COMPOUNDS Transition metal compounds display a wide variety of colors and many of these compounds are used as artist's pigments (e.g., copper phthalocyanine,

### COLORS WE CONSUME A spectroscopic analysis of FD&C food colors in soda pop

COLORS WE CONSUME A spectroscopic analysis of FD&C food colors in soda pop LAB VIS 12 Used with permission by Gary Krenzer, Mercer High School, Dr. Charles Kriley and Dr. Harold Condor, Grove City College.

### Chemistry 111 Laboratory Experiment 7: Determination of Reaction Stoichiometry and Chemical Equilibrium

Chemistry 111 Laboratory Experiment 7: Determination of Reaction Stoichiometry and Chemical Equilibrium Introduction The word equilibrium suggests balance or stability. The fact that a chemical reaction

### Chlorine, Total. DPD Method 1 Method 10101 0.09 to 5.00 mg/l Cl 2 Test 'N Tube Vials. Test preparation. Instrument-specific information

Chlorine, Total DOC316.53.01028 DPD Method 1 Method 10101 0.09 to 5.00 mg/l Cl 2 Test 'N Tube Vials Scope and application: For testing higher levels of total (free plus combined) chlorine in drinking water,

### 2C: One in a Million. Part 1: Making solutions. Name: Section: Date: Materials

Name: Section: Date: 2C: One in a Million Drinking water can contain up to 1.3 parts per million (ppm) of copper and still be considered safe. What does parts per million mean? Both living things and the

### Be sure to staple your graph to the handout!

CHEM 151 EMISSION AND ABSORPTION SPECTROSCOPY Winter 2009 Fill-in Prelab attached (p 13) Stamp Here Name Partner Lecturer Be sure to staple your graph to the handout! Introduction Date You have now observed

### BCH 312. Biochemical Calculations [Practical] Nora Aljebrin

+ BCH 312 Biochemical Calculations [Practical] Nora Aljebrin Office: Building 5, 3 rd floor, 5T267 Website: www.fac.ksu.edu.sa/naljebrin E.mail: naljebrin@ksu.edu.sa + Mark Distribution Report [ 5 Marks

### Acid Base Titrations

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

### Experiment C-31 Color Absorption

1 Experiment C-31 Color Absorption Objectives To understand the concepts of light waves and color. To investigate how red, green and blue liquids absorb light of different wavelengths. To learn about colorimeter