Concept explainers
Interpretation:
The energy of a single photon in joules and the energy of a mole of photons in
Concept introduction:
A small packet of energy is known as the quanta. Light is emitted in the form of quanta or photons. The Planck’s law gives the relation between the energy and wavelength, frequency and wavenumber.
Answer to Problem 9.40E
The energy of single photon in joules and the energy of a mole of photons in
The shorter wavelength radiations are more dangerous because these radiations transmit more energy.
Explanation of Solution
The energy of single photon in joules is calculated by the formula,
Where,
•
•
•
The energy of a mole of photons in
Where,
•
•
The given wavelength of light is
Substitute the value of
Thus, the energy of single photon in joules is
Substitute the value of
Thus, the energy of a mole of photons in
The given wavelength of light is
Substitute the value of
Thus, the energy of single photon in joules is
Substitute the value of
Thus, the energy of a mole of photons in
The given wavelength of light is
Substitute the value of
Thus, the energy of single photon in joules is
Substitute the value of
Thus, the energy of a mole of photons in
The given wavelength of light is
Substitute the value of
Thus, the energy of single photon in joules is
Substitute the value of
Thus, the energy of a mole of photons in
The given wavelength of light is
Substitute the value of
Thus, the energy of single photon in joules is
Substitute the value of
Thus, the energy of a mole of photons in
The given wavelength of light is
Substitute the value of
Thus, the energy of single photon in joules is
Substitute the value of
Thus, the energy of a mole of photons in
It is observed from the above calculated values that the energy of per mole for shorter wavelength radiations is higher than the energy of per mole for longer wavelength radiations. Thus, the shorter wavelength radiations are more dangerous.
The energy of single photon in joules and the energy of a mole of photons in
The shorter wavelength radiations are more dangerous because these radiations transmit more energy.
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Chapter 9 Solutions
Physical Chemistry
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