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Questions and Answers
What is the process called when an electron relaxes from a higher electronic state to a lower electronic state by emitting heat?
What is the process called when an electron relaxes from a higher electronic state to a lower electronic state by emitting heat?
What is the emission of a photon when an electron relaxes from the S1 → S0 state known as?
What is the emission of a photon when an electron relaxes from the S1 → S0 state known as?
Which of the following is NOT a way to stabilize the excited singlet state?
Which of the following is NOT a way to stabilize the excited singlet state?
What is the process of emitting radiation classified into?
What is the process of emitting radiation classified into?
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What is the process called when molecules in electronically excited states pass to a lower electronic state by colliding with other molecules?
What is the process called when molecules in electronically excited states pass to a lower electronic state by colliding with other molecules?
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What is the result of radiationless deactivation?
What is the result of radiationless deactivation?
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What is the energy level associated with the transition of π-π*?
What is the energy level associated with the transition of π-π*?
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What is the characteristic of singlet state?
What is the characteristic of singlet state?
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Why do molecules with relatively unstable excited states return to the ground state by radiationless collision deactivation?
Why do molecules with relatively unstable excited states return to the ground state by radiationless collision deactivation?
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What is the characteristic of triplet state?
What is the characteristic of triplet state?
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What is the comparative energy level of the excited triplet state versus the corresponding excited singlet state?
What is the comparative energy level of the excited triplet state versus the corresponding excited singlet state?
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Which type of molecules are diamagnetic?
Which type of molecules are diamagnetic?
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Which of the following compounds favors phosphorescence over fluorescence?
Which of the following compounds favors phosphorescence over fluorescence?
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What is the effect of increased temperature on fluorescence and phosphorescence?
What is the effect of increased temperature on fluorescence and phosphorescence?
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Why do solvents containing heavy atoms decrease fluorescence?
Why do solvents containing heavy atoms decrease fluorescence?
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What is the effect of dissolved oxygen on fluorescence and phosphorescence?
What is the effect of dissolved oxygen on fluorescence and phosphorescence?
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What type of lamp is used for scanning spectra?
What type of lamp is used for scanning spectra?
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What is the reason for the pH dependence of fluorescence in acidic or basic aromatic compounds?
What is the reason for the pH dependence of fluorescence in acidic or basic aromatic compounds?
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What is the main reason for the emission spectrum being shifted to longer wavelength?
What is the main reason for the emission spectrum being shifted to longer wavelength?
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What is the quantum yield of highly fluorescent molecules?
What is the quantum yield of highly fluorescent molecules?
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What happens to the fluorescence when the concentration of a compound becomes too large?
What happens to the fluorescence when the concentration of a compound becomes too large?
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What is the main reason for self-absorption of fluorescence?
What is the main reason for self-absorption of fluorescence?
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What type of molecular structure is ideal for fluorescence?
What type of molecular structure is ideal for fluorescence?
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What is the relationship between fluorescence and concentration when absorbance is less than 0.05?
What is the relationship between fluorescence and concentration when absorbance is less than 0.05?
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What is the purpose of using a double beam instrument in instrumental analysis?
What is the purpose of using a double beam instrument in instrumental analysis?
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What is the function of the wavelength selector in instrumental analysis?
What is the function of the wavelength selector in instrumental analysis?
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What type of detector is used in instrumental analysis due to the low intensity of emitted radiation?
What type of detector is used in instrumental analysis due to the low intensity of emitted radiation?
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Why is the detector placed at a right angle to the cuvette in instrumental analysis?
Why is the detector placed at a right angle to the cuvette in instrumental analysis?
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For nonfluorescent substances, what is the method used to induce fluorescence?
For nonfluorescent substances, what is the method used to induce fluorescence?
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What is the purpose of constructing a calibration curve in instrumental analysis?
What is the purpose of constructing a calibration curve in instrumental analysis?
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