Friday, March 20, 2020

Essay about Kiumarsi CHY242 W15 Chapter 15

Essay about Kiumarsi CHY242 W15 Chapter 15 Essay about Kiumarsi CHY242 W15 Chapter 15 CHY242 Organic Chemistry II Chapter 15 Infrared Spectroscopy & Mass Spectrometry Amir Kiumarsi 15.1 Introduction to Spectroscopy 15.2 IR Spectroscopy 15.3 Signal Characteristics: Wavenumber 15.4 Signal Characteristics: Intensity 15.5 Signal Characteristics: Shape 15.6 Analyzing an IR Spectrum 15.7 Using IR to Distinguish between Two Compounds 15.8 Introduction to Mass Spectrometry 15.9 Analyzing the (M)+ Peak 15.10 Analyzing the (M+1) + Peak 15.11 Analyzing the (M+2) + Peak 15.12 Analyzing the Fragments Chapter 10/2 15.14 Gas Chromatography- Mass Spectrometry 15.1 Introduction to Spectroscopy Wavelength Frequency Chapter 13/3 15.1 Introduction to Spectroscopy There are many wavelengths of light that cannot be observed with your eyes. Copyright 2012 John Wiley & Sons, Inc. 15-4 Klein, Organic Chemistry 1e 15.1 Introduction to Spectroscopy When light interacts with molecules, the effect depends on the wavelength of light used. This chapter focuses on IR spectroscopy. Copyright 2012 John Wiley & Sons, Inc. 15-5 Klein, Organic Chemistry 1e Interaction Electromagnetic Radiation with Molecules Chapter 13/6 Electromagnetic Spectrum Absorption Spectra Chapter 13/7 Electromagnetic Spectrum Absorption Spectra Chapter 13/8 Interaction Electromagnetic Radiation with Molecules p. 503 Infrared Spectroscopy Wavenumber is the reciprocal of wavelength Fig. 13-3, p. 505 Vibration in Organic Molecules Vibration of Water (H2O): youtube.com/watch?v=1uE2lvVkKW0 Vibrations of Molecules: youtube.com/watch?v=3RqEIr8NtMI Chapter 10/11 Â © 2012 Pearson Education, Inc. 15.2 IR Spectroscopy Molecular bonds can vibrate by stretching or by bending in a number of ways. This chapter will focus mostly on stretching frequencies. Some night vision goggles can detect IR light that is emitted. Copyright 2012 John Wiley & Sons, Inc. 15-12 Klein, Organic Chemistry 1e 15.2 IR Spectroscopy The energy necessary to cause vibration depends on the type of bond. Copyright 2012 John Wiley & Sons, Inc. 15-13 Klein, Organic Chemistry 1e 15.2 IR Spectroscopy In the IR spectrum: % transmittance Wavenumber Copyright 2012 John Wiley & Sons, Inc. 15-14 Klein, Organic Chemistry 1e 15.2 IR Spectroscopy IR spectrum characteristics WAVENUMBER INTENSITY Strong, Moderate, weak SHAPE Copyright 2012 John Wiley & Sons, Inc. 15-15 Klein, Organic Chemistry 1e 15.3 IR Signal Wavenumber The WAVENUMBER for a stretching vibration depends on the bond strength and the mass of the atoms: bonded together Copyright 2012 John Wiley & Sons, Inc. 15-16 Klein, Organic Chemistry 1e 15.3 IR Signal Wavenumber Rationalize the trends below using the wavenumber formula: 1. 2. Copyright 2012 John Wiley & Sons, Inc. 15-17 Klein, Organic Chemistry 1e 15.3 IR Signal Wavenumber The wavenumber formula and empirical observations allow us to designate regions as representing specific types of bonds. Copyright 2012 John Wiley & Sons, Inc. 15-18 Klein, Organic Chemistry 1e 15.3 IR Signal Wavenumber region above 1500 cm-1 is called the diagnostic region. The region below 1500 cm-1 is called the fingerprint region. Copyright 2012 John Wiley & Sons, Inc. 15-19 Klein, Organic Chemistry 1e 15.3 IR Signal Wavenumber Analyze the diagnostic and fingerprint regions below. Copyright 2012 John Wiley & Sons, Inc. 15-20 Klein, Organic Chemistry 1e 15.3 IR Signal Wavenumber Analyze the diagnostic and fingerprint regions below. Copyright 2012 John Wiley & Sons, Inc. 15-21 Klein, Organic Chemistry 1e 15.3 IR Signal Wavenumber Compare the IR spectra. Copyright 2012 John Wiley & Sons, Inc. 15-22 Klein, Organic Chemistry 1e 15.3 IR Signal Wavenumber Compare the IR stretching wavenumbers below. Are the differences due to mass or bond strength? Which bond is strongest, and WHY? Copyright 2012 John Wiley & Sons, Inc. 15-23 Klein, Organic Chemistry 1e

Wednesday, March 4, 2020

Homophone for Band

Homophone for Band The words band and banned  are  homophones: they sound alike but have different meanings. Homophone for Band As a noun, band refers to a musical group or to any group of people joined for a common purpose. In addition, the noun band means a ring, a restraint, a belt, or a specific range of wavelengths or radio frequencies. As a verb, band means to mark with a band or to unite for a common purpose (band together). Banned is the past and past-participle form of the verb to ban, which means to forbid or prohibit. Examples Whenever possible, the individual members of the band travel from gig to gig by rented car.​The diadem is a band of gold more than an inch in width and eighteen inches in length.​The demand for new radio stations in the 1960s prompted the FCC to push new licensees into the FM band.​In 1926, H.L. Mencken was arrested in Boston for selling a banned copy of the American Mercury magazine. Practice (a) Chuck and his friends formed a rock _____, but they had trouble finding an instrument for Amos to play.(b) My father used to hide _____ books in a little vault he had built in the basement.(c) The rival factions were forced to _____ together to protect their homes against a new enemy. Answers (a) Chuck and his friends formed a rock  band, but they had trouble finding an instrument for Amos to play.(b) My father used to hide  banned  books in a little vault he had built in the basement.(c) The rival factions were forced to  band  together to protect their homes against a new enemy. Answers to Practice Exercises: Band and Banned (a) Chuck and his friends formed a rock band, but they had trouble finding an instrument for Amos to play.(b) My father used to hide banned books in a little vault he had built in the basement.(c) The rival factions were forced to band together to protect their homes against a new enemy. Glossary of Usage: Index of Commonly Confused Words