1901 Application of Spectrophotometry

Size: px
Start display at page:

Download "1901 Application of Spectrophotometry"

Transcription

1 1901 Application of Spectrophotometry Chemical Analysis Problem: 1 Application of Spectroscopy

2 Organic Compounds Organic compounds with single bonds absorb in the UV region because electrons from single bonds are tightly held. Electrons in double or triple bonds absorb in the UV and visible region are called chromophores. Chromophores are unsaturated organic functional groups that red shifts if conjugation of two or more chromophores are in a compound. 2 Application of Spectroscopy

3 Inorganic Compounds Inorganic compounds involve transition between d-orbitials. Crystal field theory explains the nature of the transition. Absorption spectra of ion of the lanthanide and actinide series differ substantially from transition metals. 3 Application of Spectroscopy

4 Charge Transfer Transitions An important class of absorption is the chargetransfer which originates from electron-donor group bonded to an electron acceptor group. The excited state results in an internal oxidation/reduction process. Examples are phenolic complex of iron, pyridyl complexes, the 1,10-phenanthroline complexes, the iodide complex of molecular iodine and the ferro/ferricyanide complex. Some of these transition originate from metal to ligand charge transfer and others are ligand to metal charge transfer. In some charge transfer process, the excited complex dissociate and produce photochemical oxidation/reduction products. Iridium bipyridine complexes 4 Application of Spectroscopy

5 UV-Vis Spectral Limits UV-Vis spectra do not have sufficient fine structure to permit unambiguous identification. UV-Vis must be supplemented with other physical or chemical evidence. For qualitative analysis, it is important that the solvent is transparent in the region of the chromophores. The table shows the window for various solvents. Effect of slit width. The spectra shows cytochrome C under four spectral bandwidth (1) 20 nm, (2) 10 nm, (3) 5 nm, and (4) 1 nm. Scattering should also be corrected for. In some instances, false peak will be observed because of operation of the spectrometer to its wavelength extreme. Shown is the spectra of cerium(iv) obtained in glass optical (A) and in quartz (B). 5 Application of Spectroscopy

6 Versatility of UV-Vis spectroscopy Most important characteristics of spectrophotometric and photometric methods are: 1. Wide applicability - Inorganic, organic and biochemicals can be analyzed using this technique. 90% of analysis in lab are based on UV-Vis spectroscopy. 2. High Sensitivity - Analysis can be performed with dilute solutions, 10-4 to 10-5 M and at times 10-7 M 3. Moderately high selectivity - Can perform analysis without interference of solvent or other chemicals. 4. Good accuracy - The relative error in the technique is in the order of 1% - 5% which can be improved to 0.1 % 5. Ease of convenience - One of the easiest technique to use with minimal setup. The analysis can also be automated. 6 Application of Spectroscopy

7 Application to Absorbing and nonabsorbing species Absorbing Species - Ideal technique if the chemical being analyzed absorbs in region that can be detected. Nonabsorbing speices - Chemicals that do not absorb, can be reacted with chromophoric reagents to yield products that can be analyze using UV-Vis spectroscopy. Typical chelating reagent for absorption (a) diethyldithicarbamante (b) Diphenylthiocarbazone 7 Application of Spectroscopy

8 Procedural Details Things to consider to yield reliable results in absorption spectroscopy: Wavelength selector - Maximum sensitivity yield good results if wavelength is used in which the absorbance is the largest. Absorbances factors - Factors such as solvent, ph, temperature, ionic strength... must be controlled to minimize complication of spectra. Concentration relationship - Standardization plots must match as close as possible the condition of chemical being analyzed. Standard addition - Matrix effect of can be minimized by introducing into the standards species that approximate the amounts found in the sample via standard addition. Analysis of mixture - Total absorbance features overlap linearly for two or more components. In principle, the components can be separated to their individual components. 8 Application of Spectroscopy

9 Instrumental Uncertainties Accuracy and precision of spectrophotometric analysis limited by indeterminate errors. These errors are summarized in the following table. A B C Error in the measurements of T (transmittance) is constant and independent of the magnitude of T. The type of instrument may give rise to error in the meter read out. Above are graphs showing the error curves for various categories of instrument uncertainties. 9 Application of Spectroscopy

10 Error in Transmittance for Different Instruments The RSD analysis for the two instruments show that absorbance lower than 0.1 are not reliable and should be avoided. The reason is the concentration is directly proportional to the difference in intensity of Po and Pi, through A = log Po -log Pi. At low concentrations, log P is nearly large as Po and a small difference in large numbers lead to big errors. Note as well that at absorbance higher than 1.2 is also not reliable and that is because the power of the beam is so low that it cannot be measured accurately. Experiment curves relating relative concentrations uncertainties to absorbance for two spectrometers. Data obtained with (a) Spectronic 20 and (b) a Cary 118 spectrophotometer. 10 Application of Spectroscopy

11 Photometric and Spectrophotometric Titrations Equivalent points in titration can be determine by spectrophotometric analysis. Analysis requires that one or more of the reactant or product shows absorbance features. Molar absorptivites of the analyte titrated, the product, and the titrant are e A, e P and e T respectively. Photometric titration curve at 745 nm to 100mL of a solution that was M in Bi 3+ and Cu Application of Spectroscopy

12 Analysis of Complex ions Composition of a complex in solution can be determined without actually isolating the complex as a pure compound. The techniques used for such studies are (1) method of continuous variations, (2) the mole-ratio method, and (3) the slope-ratio method. Continuous variation: Method in which the cation and ligand in solutions have identical analytical concentrations with total volume and moles of reactant constant but mole ratio of reactants systematically varied. In the graph shown, the curve maxima is the result of incompleteness of the complexformation reaction. Mole-ratio: Method in which analytical concentration of one reactant (usually cation) is held constant with variation of other reactant. Slope-ratio : Method linear regression is used with Beer s Law. The method assumes (1) complex-formation reaction is complete with excess of either reactant. (2) Beer s Law is obeyed. (3) Complex absorbs at desired wavelength. 12 Application of Spectroscopy

13 Infrared Spectroscopy Versatile technique that provides molecular structure information. This makes the technique optimal for qualitative analyses but poor for quantitative analyses. The energy of infrared can excite vibration and rotational transitions, but are not sufficient for electronic transitions. Samples in the solid, liquid and gas phase can be analyzed. 13 Application of Spectroscopy

14 IR Instrumentation There are three types of IR instruments: dispersive spectrometers, Fourier-Transformed (FTIR), and filter photometers. The first two provide complete spectral analysis with the filter photometer designed for quantitative analysis. Filter Photometers: General use to monitor air particulates and can measure amounts of particles in the gas phase. Dispersive Instruments: Double beam in which samples are placed between light source and monochromator. The radiation source is generally thermal with the detectors sensitive to the heat rather hand photons. Fourier Transformed: High speed with great resolution because all wavelengths are detected and measured simultaneously using a Michelson interferometer. The basic idea of this techniques is that the source signal is modulated and passed through the source sample. The resulting signal is an interferogram that is Fourier Transformed to yield all the frequencies that was absorbed by the sample. 14 Application of Spectroscopy

15 Spectra Interpretation IR frequencies for various functional groups 15 Application of Spectroscopy

16 Quantitative Applications of IR IR spectra consist of bands that correspond to infrared absorption. Bands in the shorter wavelength, mm ( wavenumbers, cm -1 ), are characteristics of functional groups in the structure of the chemical. To truly identify chemical the whole spectrum mm must be analyzed. It may be possible to compare the spectrum to published results in the literature Application of Spectroscopy

Chapter 13 An Introduction to Ultraviolet/Visible Molecular Absorption Spectrometry

Chapter 13 An Introduction to Ultraviolet/Visible Molecular Absorption Spectrometry Chapter 13 An Introduction to Ultraviolet/Visible Molecular Absorption Spectrometry 13A Measurement Of Transmittance and Absorbance Absorption measurements based upon ultraviolet and visible radiation

More information

Spectroscopy. Page 1 of 8 L.Pillay (2012)

Spectroscopy. Page 1 of 8 L.Pillay (2012) Spectroscopy Electromagnetic radiation is widely used in analytical chemistry. The identification and quantification of samples using electromagnetic radiation (light) is called spectroscopy. Light has

More information

levels. The signal is either absorbance vibrational and rotational energy levels or percent transmittance of the analyte

levels. The signal is either absorbance vibrational and rotational energy levels or percent transmittance of the analyte 1 In this chapter, absorption by molecules, rather than atoms, is considered. Absorption in the ultraviolet and visible regions occurs due to electronic transitions from the ground state to excited state.

More information

Spectrophotometry. Introduction

Spectrophotometry. Introduction Spectrophotometry Spectrophotometry is a method to measure how much a chemical substance absorbs light by measuring the intensity of light as a beam of light passes through sample solution. The basic principle

More information

9/28/10. Visible and Ultraviolet Molecular Spectroscopy - (S-H-C Chapters 13-14) Valence Electronic Structure. n σ* transitions

9/28/10. Visible and Ultraviolet Molecular Spectroscopy - (S-H-C Chapters 13-14) Valence Electronic Structure. n σ* transitions Visible and Ultraviolet Molecular Spectroscopy - (S-H-C Chapters 13-14) Electromagnetic Spectrum - Molecular transitions Widely used in chemistry. Perhaps the most widely used in Biological Chemistry.

More information

09/05/40 MOLECULAR ABSORPTION METHODS

09/05/40 MOLECULAR ABSORPTION METHODS MOLECULAR ABSORPTION METHODS Absorption spectroscopy refers to spectroscopic techniques that measure the absorption of radiation, as a function of wavelength ( absorption spectrum ), due to its interaction

More information

Ultraviolet-Visible Spectroscopy

Ultraviolet-Visible Spectroscopy Ultraviolet-Visible Spectroscopy Introduction to UV-Visible Absorption spectroscopy from 160 nm to 780 nm Measurement of transmittance Conversion to absorbance * A=-logT=εbc Measurement of transmittance

More information

Advanced Pharmaceutical Analysis

Advanced Pharmaceutical Analysis Lecture 2 Advanced Pharmaceutical Analysis IR spectroscopy Dr. Baraa Ramzi Infrared Spectroscopy It is a powerful tool for identifying pure organic and inorganic compounds. Every molecular compound has

More information

Chem 310 rd. 3 Homework Set Answers

Chem 310 rd. 3 Homework Set Answers -1- Chem 310 rd 3 Homework Set Answers 1. A double line labeled S 0 represents the _ground electronic_ state and the _ground vibrational_ state of a molecule in an excitation state diagram. Light absorption

More information

Advanced Analytical Chemistry

Advanced Analytical Chemistry 84.514 Advanced Analytical Chemistry Part III Molecular Spectroscopy (continued) Website http://faculty.uml.edu/david_ryan/84.514 http://www.cem.msu.edu/~reusch/virtualtext/ Spectrpy/UV-Vis/spectrum.htm

More information

Course: M.Sc (Chemistry) Analytical Chemistry Unit: III

Course: M.Sc (Chemistry) Analytical Chemistry Unit: III Course: M.Sc (Chemistry) Analytical Chemistry Unit: III Syllabus: Principle of spectrophotometry Types of spectrophotometer Applications - Dissociation constants of an indicator simultaneous spectrophotometric

More information

Reference literature. (See: CHEM 2470 notes, Module 8 Textbook 6th ed., Chapters )

Reference literature. (See: CHEM 2470 notes, Module 8 Textbook 6th ed., Chapters ) September 17, 2018 Reference literature (See: CHEM 2470 notes, Module 8 Textbook 6th ed., Chapters 13-14 ) Reference.: https://slideplayer.com/slide/8354408/ Spectroscopy Usual Wavelength Type of Quantum

More information

Ultraviolet-Visible and Infrared Spectrophotometry

Ultraviolet-Visible and Infrared Spectrophotometry Ultraviolet-Visible and Infrared Spectrophotometry Ahmad Aqel Ifseisi Assistant Professor of Analytical Chemistry College of Science, Department of Chemistry King Saud University P.O. Box 2455 Riyadh 11451

More information

Spectroscopy Primer. for ultraviolet and visible absorbance spectroscopy. by Stephanie Myers Summer 2015

Spectroscopy Primer. for ultraviolet and visible absorbance spectroscopy. by Stephanie Myers Summer 2015 Spectroscopy Primer for ultraviolet and visible absorbance spectroscopy by Stephanie Myers Summer 2015 Abstract: An overview of uv vis absorbance spectroscopy including Beer s Law, calibration curves,

More information

Ultraviolet-Visible and Infrared Spectrophotometry

Ultraviolet-Visible and Infrared Spectrophotometry Ultraviolet-Visible and Infrared Spectrophotometry Ahmad Aqel Ifseisi Assistant Professor of Analytical Chemistry College of Science, Department of Chemistry King Saud University P.O. Box 2455 Riyadh 11451

More information

Reflection = EM strikes a boundary between two media differing in η and bounces back

Reflection = EM strikes a boundary between two media differing in η and bounces back Reflection = EM strikes a boundary between two media differing in η and bounces back Incident ray θ 1 θ 2 Reflected ray Medium 1 (air) η = 1.00 Medium 2 (glass) η = 1.50 Specular reflection = situation

More information

1 WHAT IS SPECTROSCOPY?

1 WHAT IS SPECTROSCOPY? 1 WHAT IS SPECTROSCOPY? 1.1 The Nature Of Electromagnetic Radiation Anyone who has been sunburnt will know that light packs a punch: in scientific terms, it contains considerable amounts of energy. All

More information

An Introduction to Ultraviolet-Visible Molecular Spectrometry (Chapter 13)

An Introduction to Ultraviolet-Visible Molecular Spectrometry (Chapter 13) An Introduction to Ultraviolet-Visible Molecular Spectrometry (Chapter 13) Beer s Law: A = -log T = -logp 0 / P = e x b x C See Table 13-1 for terms. In measuring absorbance or transmittance, one should

More information

Chapter 4 Ultraviolet and visible spectroscopy Molecular Spectrophotometry

Chapter 4 Ultraviolet and visible spectroscopy Molecular Spectrophotometry Chapter 4 Ultraviolet and visible spectroscopy Molecular Spectrophotometry Properties of light Electromagnetic radiation and electromagnetic spectrum Absorption of light Beer s law Limitation of Beer s

More information

Answers to spectroscopy questions. 1. Consider the spectrum below. Questions a f refer to this spectrum.

Answers to spectroscopy questions. 1. Consider the spectrum below. Questions a f refer to this spectrum. Answers to spectroscopy questions. 1. Consider the spectrum below. Questions a f refer to this spectrum. a. Is the spectrum above a band spectrum or a line spectrum? This is a band spectra, there are what

More information

Chem Homework Set Answers

Chem Homework Set Answers Chem 310 th 4 Homework Set Answers 1. Cyclohexanone has a strong infrared absorption peak at a wavelength of 5.86 µm. (a) Convert the wavelength to wavenumber.!6!1 8* = 1/8 = (1/5.86 µm)(1 µm/10 m)(1 m/100

More information

MOLECULAR ABSORPTION METHODS

MOLECULAR ABSORPTION METHODS MOLECULAR ABSORPTION METHODS Absorption spectroscopy refers to spectroscopic techniques that measure the absorption of radiation, as a function of wavelength ( absorption spectrum ), due to its interaction

More information

Lab #12: Determination of a Chemical Equilibrium Constant

Lab #12: Determination of a Chemical Equilibrium Constant Lab #12: 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 information

Visible and IR Absorption Spectroscopy. Andrew Rouff and Kyle Chau

Visible and IR Absorption Spectroscopy. Andrew Rouff and Kyle Chau Visible and IR Absorption Spectroscopy Andrew Rouff and Kyle Chau The Basics wavelength= (λ) original intensity= Ι o sample slab thickness= dl Final intensity= I f ε = molar extinction coefficient -di=

More information

2001 Spectrometers. Instrument Machinery. Movies from this presentation can be access at

2001 Spectrometers. Instrument Machinery. Movies from this presentation can be access at 2001 Spectrometers Instrument Machinery Movies from this presentation can be access at http://www.shsu.edu/~chm_tgc/sounds/sound.html Chp20: 1 Optical Instruments Instrument Components Components of various

More information

Chapter 17: Fundamentals of Spectrophotometry

Chapter 17: Fundamentals of Spectrophotometry Chapter 17: Fundamentals of Spectrophotometry Spectroscopy: the science that deals with interactions of matter with electromagnetic radiation or other forms energy acoustic waves, beams of particles such

More information

CHEM*3440. Photon Energy Units. Spectrum of Electromagnetic Radiation. Chemical Instrumentation. Spectroscopic Experimental Concept.

CHEM*3440. Photon Energy Units. Spectrum of Electromagnetic Radiation. Chemical Instrumentation. Spectroscopic Experimental Concept. Spectrum of Electromagnetic Radiation Electromagnetic radiation is light. Different energy light interacts with different motions in molecules. CHEM*344 Chemical Instrumentation Topic 7 Spectrometry Radiofrequency

More information

Chemistry Instrumental Analysis Lecture 15. Chem 4631

Chemistry Instrumental Analysis Lecture 15. Chem 4631 Chemistry 4631 Instrumental Analysis Lecture 15 IR Instruments Types of Instrumentation Dispersive Spectrophotometers (gratings) Fourier transform spectrometers (interferometer) Single beam Double beam

More information

PAPER No. 12: ORGANIC SPECTROSCOPY MODULE No. 7: Instrumentation for IR spectroscopy

PAPER No. 12: ORGANIC SPECTROSCOPY MODULE No. 7: Instrumentation for IR spectroscopy KNOW MORE Web links https://en.wikipedia.org/wiki/infrared_ http://hiq.lindegas.com/en/analytical_methods/infrared_/non_dispersive_infrared.html http://blamp.sites.truman.edu/files/2012/11/322-ir-and-ftir.pdf

More information

Compact Knowledge: Absorbance Spectrophotometry. Flexible. Reliable. Personal.

Compact Knowledge: Absorbance Spectrophotometry. Flexible. Reliable. Personal. L A B O R A T O R Y C O M P E T E N C E Compact Knowledge: Absorbance Spectrophotometry Flexible. Reliable. Personal. The interaction of light with molecules is an essential and well accepted technique

More information

Application of IR Raman Spectroscopy

Application of IR Raman Spectroscopy Application of IR Raman Spectroscopy 3 IR regions Structure and Functional Group Absorption IR Reflection IR Photoacoustic IR IR Emission Micro 10-1 Mid-IR Mid-IR absorption Samples Placed in cell (salt)

More information

Determining Riboflavin Content in a Multivitamin: Things to do before the lab

Determining Riboflavin Content in a Multivitamin: Things to do before the lab Determining Riboflavin Content in a Multivitamin: Things to do before the lab Calculate everything you can that you can in advance Step 1: Calculate the dilution of a 4.0 M solution to 1 L of a 0.02 M

More information

10/2/2008. hc λ. νλ =c. proportional to frequency. Energy is inversely proportional to wavelength And is directly proportional to wavenumber

10/2/2008. hc λ. νλ =c. proportional to frequency. Energy is inversely proportional to wavelength And is directly proportional to wavenumber CH217 Fundamentals of Analytical Chemistry Module Leader: Dr. Alison Willows Electromagnetic spectrum Properties of electromagnetic radiation Many properties of electromagnetic radiation can be described

More information

PAPER No. 12: ORGANIC SPECTROSCOPY MODULE No. 4: Basic principles and Instrumentation for IR spectroscopy

PAPER No. 12: ORGANIC SPECTROSCOPY MODULE No. 4: Basic principles and Instrumentation for IR spectroscopy Subject Chemistry Paper No and Title Module No and Title Module Tag Paper 12: Organic Spectroscopy Module 4: Basic principles and Instrumentation for IR spectroscopy CHE_P12_M4_e-Text TABLE OF CONTENTS

More information

Concepts, Techniques. Concepts, Techniques 9/11/2012. & Beer s Law. For a simple, transparent, COLORED material, e.g. ROYGBV

Concepts, Techniques. Concepts, Techniques 9/11/2012. & Beer s Law. For a simple, transparent, COLORED material, e.g. ROYGBV 9//22 OBJECTIVES Spectrophotometry of Food Dyes & Beer s Law Last Update: 9//22 9:54 AM What is the quantitative basis for the color of substances? How is the absorption/transmission of light measured?

More information

Ch 313 FINAL EXAM OUTLINE Spring 2010

Ch 313 FINAL EXAM OUTLINE Spring 2010 Ch 313 FINAL EXAM OUTLINE Spring 2010 NOTE: Use this outline at your own risk sometimes a topic is omitted that you are still responsible for. It is meant to be a study aid and is not meant to be a replacement

More information

UV-Vis Absorption Experiment 5: Beer- Lambert Law and the Temperature Dependence of the Crystal Violet- Sodium Hydroxide Reaction

UV-Vis Absorption Experiment 5: Beer- Lambert Law and the Temperature Dependence of the Crystal Violet- Sodium Hydroxide Reaction 1 UV-Vis Absorption Experiment 5: Beer- Lambert Law and the Temperature Dependence of the Crystal Violet- Sodium Hydroxide Reaction Overview In Part A of this experiment, the absorption behaviour of crystal

More information

Paper: 12, Organic Spectroscopy Module: 5, Applications of UV spectroscopy

Paper: 12, Organic Spectroscopy Module: 5, Applications of UV spectroscopy Subject Chemistry Paper No and Title Module No and Title Module Tag Paper 12: Organic Spectroscopy Applications of UV-visible Spectroscopy CHE_P12_M5 TABLE OF CONTENTS 1. Learning Outcomes 2. Introduction

More information

Chem 155 Quiz 3 Review Topics: Quiz 3 outline

Chem 155 Quiz 3 Review Topics: Quiz 3 outline Quiz 3 outline 1. Atomic absorption spectrometry a. Principles of FAAS where selectivity and sensitivity arise b. Spectrometer design c. Atomization processes d. Sensitvitiy and atomization: protecting

More information

Chemistry Instrumental Analysis Lecture 11. Chem 4631

Chemistry Instrumental Analysis Lecture 11. Chem 4631 Chemistry 4631 Instrumental Analysis Lecture 11 Molar Absorptivities Range 0 to 10 5 Magnitude of e depends on capture cross section of the species and probability of the energy-absorbing transition. e

More information

Questions on Instrumental Methods of Analysis

Questions on Instrumental Methods of Analysis Questions on Instrumental Methods of Analysis 1. Which one of the following techniques can be used for the detection in a liquid chromatograph? a. Ultraviolet absorbance or refractive index measurement.

More information

25 Instruments for Optical Spectrometry

25 Instruments for Optical Spectrometry 25 Instruments for Optical Spectrometry 25A INSTRUMENT COMPONENTS (1) source of radiant energy (2) wavelength selector (3) sample container (4) detector (5) signal processor and readout (a) (b) (c) Fig.

More information

Basics of UV-Visible Spectroscopy *

Basics of UV-Visible Spectroscopy * OpenStax-CNX module: m34525 1 Basics of UV-Visible Spectroscopy * Brittany L. Oliva-Chatelain Andrew R. Barron This work is produced by OpenStax-CNX and licensed under the Creative Commons Attribution

More information

Spectrophotometric Determination of Iron

Spectrophotometric Determination of Iron Spectrophotometric Determination of Iron INTRODUCTION Many investigations of chemical species involve the interaction between light and matter. One class of these investigations, called absorbance spectrophotometry,

More information

GENERAL PHARMACOPOEIA MONOGRAPH

GENERAL PHARMACOPOEIA MONOGRAPH MINISTRY OF HEALTH OF THE RUSSIAN FEDERATION GENERAL PHARMACOPOEIA MONOGRAPH Spectrophotometry in the ultraviolet GPM.1.2.1.1.0003.15 and visible spectral regions Replaces the SPRF X GPM, SPRF XI GPM,

More information

2 SPECTROSCOPIC ANALYSIS

2 SPECTROSCOPIC ANALYSIS 2 SPECTROSCOPIC ANALYSIS 2.1 Introduction Chemical analysis falls into two basic categories: qualitative what is present quantitative how much is present Spectroscopy is capable of both types of analysis,

More information

Design and Development of a Smartphone Based Visible Spectrophotometer for Analytical Applications

Design and Development of a Smartphone Based Visible Spectrophotometer for Analytical Applications Design and Development of a Smartphone Based Visible Spectrophotometer for Analytical Applications Bedanta Kr. Deka, D. Thakuria, H. Bora and S. Banerjee # Department of Physicis, B. Borooah College, Ulubari,

More information

R O Y G B V. Spin States. Outer Shell Electrons. Molecular Rotations. Inner Shell Electrons. Molecular Vibrations. Nuclear Transitions

R O Y G B V. Spin States. Outer Shell Electrons. Molecular Rotations. Inner Shell Electrons. Molecular Vibrations. Nuclear Transitions Spin States Molecular Rotations Molecular Vibrations Outer Shell Electrons Inner Shell Electrons Nuclear Transitions NMR EPR Microwave Absorption Spectroscopy Infrared Absorption Spectroscopy UV-vis Absorption,

More information

Analytical Technologies in Biotechnology Prof. Dr. Ashwani K Sharma Department of Biotechnology Indian Institute of Technology, Roorkee

Analytical Technologies in Biotechnology Prof. Dr. Ashwani K Sharma Department of Biotechnology Indian Institute of Technology, Roorkee Analytical Technologies in Biotechnology Prof. Dr. Ashwani K Sharma Department of Biotechnology Indian Institute of Technology, Roorkee Module - 6 Spectroscopic Techniques Lecture - 2 UV-Visible Spectroscopy

More information

3 - Atomic Absorption Spectroscopy

3 - Atomic Absorption Spectroscopy 3 - Atomic Absorption Spectroscopy Introduction Atomic-absorption (AA) spectroscopy uses the absorption of light to measure the concentration of gas-phase atoms. Since samples are usually liquids or solids,

More information

Chapter 17: Fundamentals of Spectrophotometry

Chapter 17: Fundamentals of Spectrophotometry Chapter 17: Fundamentals of Spectrophotometry Spectroscopy: the science that deals with interactions of matter with electromagnetic radiation or other forms energy acoustic waves, beams of particles such

More information

Fourier Transform IR Spectroscopy

Fourier Transform IR Spectroscopy Fourier Transform IR Spectroscopy Absorption peaks in an infrared absorption spectrum arise from molecular vibrations Absorbed energy causes molecular motions which create a net change in the dipole moment.

More information

Probing Bonding Using Infrared Spectroscopy Chem

Probing Bonding Using Infrared Spectroscopy Chem Probing Bonding Using Infrared Spectroscopy Chem 112-2011 INTRODUCTION First, watch the short video on how to record an infrared spectrum using an infrared spectrometer, linked at: http://employees.oneonta.edu/viningwj/chem112/labs/ir_video/ir_video_controller.swf

More information

IR Spectrography - Absorption. Raman Spectrography - Scattering. n 0 n M - Raman n 0 - Rayleigh

IR Spectrography - Absorption. Raman Spectrography - Scattering. n 0 n M - Raman n 0 - Rayleigh RAMAN SPECTROSCOPY Scattering Mid-IR and NIR require absorption of radiation from a ground level to an excited state, requires matching of radiation from source with difference in energy states. Raman

More information

Spectroscopy Problem Set February 22, 2018

Spectroscopy Problem Set February 22, 2018 Spectroscopy Problem Set February, 018 4 3 5 1 6 7 8 1. In the diagram above which of the following represent vibrational relaxations? 1. Which of the following represent an absorbance? 3. Which of following

More information

Clinical Chemistry (CHE221) Professor Hicks Week 1. Statistics Made Slightly Less Boring and Introduction to Spectrophotometry. Accuracy vs Precision

Clinical Chemistry (CHE221) Professor Hicks Week 1. Statistics Made Slightly Less Boring and Introduction to Spectrophotometry. Accuracy vs Precision Clinical Chemistry (CHE221) Professor Hicks Week 1 Statistics Made Slightly Less Boring and Introduction to Spectrophotometry 3 Accuracy vs Precision Precision is the consistency of a measurement made

More information

Beer's Law and Data Analysis *

Beer's Law and Data Analysis * OpenStax-CNX module: m15131 1 Beer's Law and Data Analysis * Mary McHale This work is produced by OpenStax-CNX and licensed under the Creative Commons Attribution License 2.0 1 Beer's Law and Data Analysis

More information

Cork Institute of Technology. Summer 2005 Instrumental Analysis (Time: 3 Hours) Section A

Cork Institute of Technology. Summer 2005 Instrumental Analysis (Time: 3 Hours) Section A Cork Institute of Technology Higher Certificate in Science in Applied Biology Award (National Certificate in Science in Applied Biology Award) Answer FIVE questions; answer Section A, TWO questions from

More information

Instrumental Chemical Analysis

Instrumental Chemical Analysis L6 page 1 Instrumental Chemical Analysis Ultraviolet and visible spectroscopy Dr. Ahmad Najjar Philadelphia University Faculty of Pharmacy Department of Pharmaceutical Sciences 2 nd semester, 2016/2017

More information

Instrumental Chemical Analysis

Instrumental Chemical Analysis L6 page 1 Instrumental Chemical Analysis Ultraviolet and visible spectroscopy Dr. Ahmad Najjar Philadelphia University Faculty of Pharmacy Department of Pharmaceutical Sciences 2 nd semester, 2016/2017

More information

Chemistry 524--Final Exam--Keiderling Dec. 12, pm SES

Chemistry 524--Final Exam--Keiderling Dec. 12, pm SES Chemistry 524--Final Exam--Keiderling Dec. 12, 2002 --4-8 pm -- 238 SES Please answer all questions in the answer book provided. Calculators, rulers, pens and pencils are permitted plus one 8.5 x 11 sheet

More information

FTIR Spectrometer. Basic Theory of Infrared Spectrometer. FTIR Spectrometer. FTIR Accessories

FTIR Spectrometer. Basic Theory of Infrared Spectrometer. FTIR Spectrometer. FTIR Accessories FTIR Spectrometer Basic Theory of Infrared Spectrometer FTIR Spectrometer FTIR Accessories What is Infrared? Infrared radiation lies between the visible and microwave portions of the electromagnetic spectrum.

More information

Educational experiment package Volume 1. Molecular spectroscopy

Educational experiment package Volume 1. Molecular spectroscopy Educational experiment package Volume 1 Molecular spectroscopy Overview Thermo Fisher Scientific is proud to offer a variety of educational experiments for use with Fourier transform infrared (FTIR) spectrometers.

More information

Infra Red Spectroscopy

Infra Red Spectroscopy CH 2252 Instrumental Methods of Analysis Unit I Infra Red Spectroscopy M. Subramanian Assistant Professor Department of Chemical Engineering Sri Sivasubramaniya Nadar College of Engineering Kalavakkam

More information

Optical Properties of Thin Semiconductor Films

Optical Properties of Thin Semiconductor Films Optical Properties of Thin Semiconductor Films Grolik Benno,KoppJoachim October, 31st 2003 1 Introduction Optical experiments provide a good way of examining the properties of semiconductors. Particulary

More information

Skoog Chapter 7 Components of Optical Instruments

Skoog Chapter 7 Components of Optical Instruments Skoog Chapter 7 Components of Optical Instruments General Design of Optical Instruments Sources of Radiation Wavelength Selectors (Filters, Monochromators, Interferometers) Sample Containers Radiation

More information

Chem 321 Lecture 18 - Spectrophotometry 10/31/13

Chem 321 Lecture 18 - Spectrophotometry 10/31/13 Student Learning Objectives Chem 321 Lecture 18 - Spectrophotometry 10/31/13 In the lab you will use spectrophotometric techniques to determine the amount of iron, calcium and magnesium in unknowns. Although

More information

VALLIAMMAI ENGINEERING COLLEGE SRM Nagar, Kattankulathur

VALLIAMMAI ENGINEERING COLLEGE SRM Nagar, Kattankulathur VALLIAMMAI ENGINEERING COLLEGE SRM Nagar, Kattankulathur 603 203 DEPARTMENT OF ELECTRONICS AND INSTRUMENTATION ENGINEERING QUESTION BANK V SEMESTER EI6501 Analytical Instruments Regulation 2013 Academic

More information

Chem 321 Name Answer Key D. Miller

Chem 321 Name Answer Key D. Miller 1. For a reversed-phase chromatography experiment, it is noted that the retention time of an analyte decreases as the percent of acetonitrile (CH 3 CN) increases in a CH 3 CN/H 2 O mobile phase. Explain

More information

Infrared Spectroscopy: Identification of Unknown Substances

Infrared Spectroscopy: Identification of Unknown Substances Infrared Spectroscopy: Identification of Unknown Substances Suppose a white powder is one of the four following molecules. How can they be differentiated? H N N H H H H Na H H H H H A technique that is

More information

UNIT 2 UV-VISIBLE SPECTROMETRY

UNIT 2 UV-VISIBLE SPECTROMETRY Molecular Spectroscopic Methods-I UNIT 2 UV-VISIBLE SPECTROMETRY Structure 2.1 Introduction Objectives 2.2 Origin and Characteristics of UV-VIS Spectrum Origin of UV-VIS spectrum Characteristics of UV-VIS

More information

FLAME PHOTOMETRY AIM INTRODUCTION

FLAME PHOTOMETRY AIM INTRODUCTION FLAME PHOTOMETRY AIM INTRODUCTION Atomic spectroscopy is based on the absorption, emission or fluorescence process of light by atoms or elementary ions. Information for atomic scale is obtained in two

More information

Chapter 18. Fundamentals of Spectrophotometry. Properties of Light

Chapter 18. Fundamentals of Spectrophotometry. Properties of Light Chapter 18 Fundamentals of Spectrophotometry Properties of Light Electromagnetic Radiation energy radiated in the form of a WAVE caused by an electric field interacting with a magnetic field result of

More information

Spectroscopy: Introduction. Required reading Chapter 18 (pages ) Chapter 20 (pages )

Spectroscopy: Introduction. Required reading Chapter 18 (pages ) Chapter 20 (pages ) Spectroscopy: Introduction Required reading Chapter 18 (pages 378-397) Chapter 20 (pages 424-449) Spectrophotometry is any procedure that uses light to measure chemical concentrations Properties of Light

More information

SPECTROPHOTOMETRY AND SPECTROMETRY - CONCEPT AND APPLICATIONS

SPECTROPHOTOMETRY AND SPECTROMETRY - CONCEPT AND APPLICATIONS SPECTROPHOTOMETRY AND SPECTROMETRY - CONCEPT AND APPLICATIONS Renjini A 1, Dani Dileep 2 1 Assistant Professor, Department of ECE, Rajadhani Institute of Engineering and Technology, Kerala, India 2 PG

More information

Absorption photometry

Absorption photometry The light Absorption photometry Szilvia Barkó University of Pécs, Faculty of Medicines, Dept. Biophysics February 2011 Transversal wave E Electromagnetic wave electric gradient vector wavelength The dual

More information

Infrared Spectroscopy

Infrared Spectroscopy Infrared Spectroscopy IR Spectroscopy Used to identify organic compounds IR spectroscopy provides a 100% identification if the spectrum is matched. If not, IR at least provides information about the types

More information

MOLEBIO LAB #4: Using a Spectrophotometer

MOLEBIO LAB #4: Using a Spectrophotometer Introduction: Spectrophotometry MOLEBIO LAB #4: Using a Spectrophotometer Many kinds of molecules interact with or absorb specific types of radiant energy in a predictable fashion. For example, when while

More information

PART SPECTROPHOTOMETRIC STUDIES

PART SPECTROPHOTOMETRIC STUDIES PART SPECTROPHOTOMETRIC STUDIES CHAPTER General Principles of Spectrophotometry 123 In absorption spectroscopy, absorption measurements based upon ultraviolet light and visible radiation find application

More information

two slits and 5 slits

two slits and 5 slits Electronic Spectroscopy 2015January19 1 1. UV-vis spectrometer 1.1. Grating spectrometer 1.2. Single slit: 1.2.1. I diffracted intensity at relative to un-diffracted beam 1.2.2. I - intensity of light

More information

4.3A: Electronic transitions

4.3A: Electronic transitions Ashley Robison My Preferences Site Tools Popular pages MindTouch User Guide FAQ Sign Out If you like us, please share us on social media. The latest UCD Hyperlibrary newsletter is now complete, check it

More information

Glossary. Analyte - the molecule of interest when performing a quantitative analysis.

Glossary. Analyte - the molecule of interest when performing a quantitative analysis. Glossary This glossary contains definitions of many important FTIR terms. Many of the terms listed here appeared in italics in the body of the book. Words that appear in italics in the glossary are defined

More information

Modern Instrumental Methods of Analysis Prof. J. R. Mudakavi Department of Chemical Engineering Indian Institute of Science, Bangalore

Modern Instrumental Methods of Analysis Prof. J. R. Mudakavi Department of Chemical Engineering Indian Institute of Science, Bangalore Modern Instrumental Methods of Analysis Prof J R Mudakavi Department of Chemical Engineering Indian Institute of Science, Bangalore Module No # 02 Lecture No # 07 Ultraviolet and Visible Spectrophotometry

More information

Experiment 1 (Part A): Plotting the Absorption Spectrum of Iron (II) Complex with 1,10- Phenanthroline

Experiment 1 (Part A): Plotting the Absorption Spectrum of Iron (II) Complex with 1,10- Phenanthroline Experiment (Part A): Plotting the Absorption Spectrum of Iron (II) Complex with,0- Phenanthroline Background The first step of an analytical spectrophotometric procedure for quantitative determination

More information

Chemistry 524--Final Exam--Keiderling May 4, :30 -?? pm SES

Chemistry 524--Final Exam--Keiderling May 4, :30 -?? pm SES Chemistry 524--Final Exam--Keiderling May 4, 2011 3:30 -?? pm -- 4286 SES Please answer all questions in the answer book provided. Calculators, rulers, pens and pencils are permitted. No open books or

More information

Course Details. Analytical Techniques Based on Optical Spectroscopy. Course Details. Textbook. SCCH 211: Analytical Chemistry I

Course Details. Analytical Techniques Based on Optical Spectroscopy. Course Details. Textbook. SCCH 211: Analytical Chemistry I SCCH 211: Analytical Chemistry I Analytical Techniques Based on Optical Spectroscopy Course Details September 22 October 10 September 22 November 7 November 17 December 1 Topic Period Introduction to Spectrometric

More information

Electronic Excitation by UV/Vis Spectroscopy :

Electronic Excitation by UV/Vis Spectroscopy : SPECTROSCOPY Light interacting with matter as an analytical tool III Pharm.D Department of Pharmaceutical Analysis SRM College Of Pharmacy,Katankulathur Electronic Excitation by UV/Vis Spectroscopy : X-ray:

More information

Reflection = EM strikes a boundary between two media differing in η and bounces back

Reflection = EM strikes a boundary between two media differing in η and bounces back Reflection = EM strikes a boundary between two media differing in η and bounces back Incident ray θ 1 θ 2 Reflected ray Medium 1 (air) η = 1.00 Medium 2 (glass) η = 1.50 Specular reflection = situation

More information

MOLECULAR AND ATOMIC SPECTROSCOPY

MOLECULAR AND ATOMIC SPECTROSCOPY MOLECULAR AND ATOMIC SPECTROSCOPY 1. General Background on Molecular Spectroscopy 3 1.1. Introduction 3 1.2. Beer s Law 5 1.3. Instrumental Setup of a Spectrophotometer 12 1.3.1. Radiation Sources 13 1.3.2.

More information

Fourier Transform Infrared. Spectrometry

Fourier Transform Infrared. Spectrometry Fourier Transform Infrared. Spectrometry Second Editio n PETER R. GRIFFITH S JAMES A. de HASETH PREFACE x v CHAPTER 1 INTRODUCTION TO VIBRATIONAL SPECTROSCOPY 1 1.1. Introduction 1 1.2. Molecular Vibrations

More information

( ) x10 8 m. The energy in a mole of 400 nm photons is calculated by: ' & sec( ) ( & % ) 6.022x10 23 photons' E = h! = hc & 6.

( ) x10 8 m. The energy in a mole of 400 nm photons is calculated by: ' & sec( ) ( & % ) 6.022x10 23 photons' E = h! = hc & 6. Introduction to Spectroscopy Spectroscopic techniques are widely used to detect molecules, to measure the concentration of a species in solution, and to determine molecular structure. For proteins, most

More information

Beer's- Lambert Law and Standard Curves. BCH 312 [Practical]

Beer's- Lambert Law and Standard Curves. BCH 312 [Practical] Beer's- Lambert Law and Standard Curves BCH 312 [Practical] Spectrophotometer: Spectrophotometer can be used to measure the amount of light absorbed or transmitted by a solution. It consist of two parts:

More information

Evaluating Labsphere s new UV-2000

Evaluating Labsphere s new UV-2000 Ciba Grenzach GmbH Optical Spectroscopy Sabrina Siegle Dr. Wolfgang Schlenker Tel. +49 76 24 / 12-28 13 E-mail wolfgang.schlenker@ciba.com May 26, 9 Evaluating Labsphere s new UV- Abstract Labsphere s

More information

Spectrochemical methods

Spectrochemical methods Spectrochemical methods G. Galbács The interactions of radiations and matter are the subject of spectroscopy py or spectrochemical methods (also called spectrometry). Spectrochemical methods usually measure

More information

AIM To verify Beer - Lambert s law and to determine the dissociation constant (Ka) of methyl red, Spectrophotometrically.

AIM To verify Beer - Lambert s law and to determine the dissociation constant (Ka) of methyl red, Spectrophotometrically. C 141(Expt. No. ) NAME : ROLL No. : SIGNATURE : BATCH : DATE : VERIFICATION OF BEER - LAMBERT S LAW & DETERMINATION OF DISSOCIATION CONSTANT (Ka) OF METHYLRED, SPECTROPHOTOMETRICALLY AIM To verify Beer

More information

Chemistry Instrumental Analysis Lecture 18. Chem 4631

Chemistry Instrumental Analysis Lecture 18. Chem 4631 Chemistry 4631 Instrumental Analysis Lecture 18 Instrumentation Radiation sources Hollow cathode lamp Most common source Consist of W anode and a cathode sealed in a glass tube filled with Ne or Ar. Hollow

More information

Secondary Ion Mass Spectrometry (SIMS)

Secondary Ion Mass Spectrometry (SIMS) CHEM53200: Lecture 10 Secondary Ion Mass Spectrometry (SIMS) Major reference: Surface Analysis Edited by J. C. Vickerman (1997). 1 Primary particles may be: Secondary particles can be e s, neutral species

More information

Lecture 3: Light absorbance

Lecture 3: Light absorbance Lecture 3: Light absorbance Perturbation Response 1 Light in Chemistry Light Response 0-3 Absorbance spectrum of benzene 2 Absorption Visible Light in Chemistry S 2 S 1 Fluorescence http://www.microscopyu.com

More information

EXPERIMENT #3 A Beer's Law Study

EXPERIMENT #3 A Beer's Law Study OBJECTVES: EXPERMENT #3 A Beer's Law Study To operate a Spectronic 20 To convert from percent transmission to absorbance units To plot absorbance versus wavelength and find max To plot absorbance versus

More information

UV / Visible Spectroscopy. Click icon to add picture

UV / Visible Spectroscopy. Click icon to add picture UV / Visible Spectroscopy Click icon to add picture Spectroscopy It is the branch of science that deals with the study of interaction of matter with light. OR It is the branch of science that deals with

More information