1 & 2. One type of sunburn occurs when skin is exposed to UV light of wavelength in the vicinity of 310 nm. a) What is the energy of a photon of this wavelength? Express your answer in joules to three significant figures. b) What is the energy of a mole of these photons? Express your answer in joules per mole to three significant figures. c) How many photons are in a 1.10 mJ burst of this radiation? Express the number of photons to three significant figures. d) These UV photons can break chemical bonds in your skin to cause sunburn (a form of radiation damage). If the 310 nm radiation provides exactly the energy to break an average chemical bond in the skin, estimate the average energy of these bonds in kJ/mol. Express your answer in kilojoules per mole to three significant figures.

1 & 2. One type of sunburn occurs when skin is exposed to UV light of wavelength in the vicinity of 310 nm. a) What is the energy of a photon of this wavelength? Express your answer in joules to three significant figures. b) What is the energy of a mole of these photons? Express your answer in joules per mole to three significant figures. c) How many photons are in a 1.10 mJ burst of this radiation? Express the number of photons to three significant figures. d) These UV photons can break chemical bonds in your skin to cause sunburn (a form of radiation damage). If the 310 nm radiation provides exactly the energy to break an average chemical bond in the skin, estimate the average energy of these bonds in kJ/mol. Express your answer in kilojoules per mole to three significant figures.

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter20: Molecular Spectroscopy And Photochemistry

Section: Chapter Questions

Problem 5P

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