CHEM 210 TEST MODULE 3 EXAM NEWEST QUESTIONS AND ANSWERS (2023 / 2024) (VERIFIED ANSWERS

Types of AbsorptionANSWERS1. Electronic Transitions 2. Rotational Transitions 3. Vibrational Transitions Rotation WavelengthANSWERSMicrowave Vibration wavelengthANSWERSInfrared Electronic WavelengthANSWERSUV & Visible LASER AcronymANSWERSLight Amplification by Stimulated Emission of Radiation Problems with Flame Atomic AbsorptionANSWERS1. Background Absorbance 2. Spectral Interference 3. Chemical Interference 4. Ionization Interference How do we account for background absorbance?ANSWERSYou measure it and subtract it How do we account for spectral interferenceANSWERSChoose a wavelength very carefully (closely-spaced lines are often removed by a spectrometer) How do we account for chemical interferenceANSWERS1. Use a high temperature 2. Use protective and releasing agents 3. Add something which binds even tighter with the interfering substance than the substance being measured, which frees the substance being measured 4. Add something (such as EDTA) which complexes the substance being measured and prevents it from binding with the interfering chemical How do we account for ionization interferenceANSWERSAdd a high concentration of a substance which ionizes easy (i.e. an alkali metal) What are the exciting and detector wavelengths like for an excitation spectrumANSWERSthe exciting wavelength is varied and the detector wavelength is constant What are the exciting and detector wavelengths like for an emission spectrumANSWERSthe exciting wavelength is constant and the detector wavelength is varied What is ELISA?ANSWERSa substance in which each molecule of analyte bound to Substance 1 also binds to Substance 2, which is linked to an enzyme molecule. Many products are created for each analyte molecule, which amplifies the signal. Isobestic PointANSWERSthe point at which both peaks for a solution's absorbance spectrum have the same wavelength What does standard addition eliminate?ANSWERSMatrix Effects Matrix EffectANSWERSthe effects caused by substances in a compound other than the compound being measured Why is a LASER used instead of a conventional light source?ANSWERSIt has a greater intensity for fluorescence Blue Wavelength rangeANSWERS400-450 nm Green Wavelength RangeANSWERS500-550 nm Red Wavelength RangeANSWERS60