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Y-ray photons with a wavelength of 2.45x10-5 nm.

Express the energy numerically in kilojoules per mole.

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Final answer:

The energy of a photon with a wavelength of 2.45x10-5 nm can be calculated using the formula E = hf, where h is Planck's constant and f is the frequency. By converting the wavelength to frequency using the equation c = λf, we can find the frequency and then calculate the energy. The energy of the photon is 1.342x10-40 kJ/mol.

Step-by-step explanation:

The energy of a photon can be calculated using the formula E = hf, where E is the energy, h is Planck's constant, and f is the frequency of the photon. To convert the wavelength to frequency, we can use the equation c = λf, where c is the speed of light and λ is the wavelength. By substituting the given wavelength of 2.45x10-5 nm (which is equivalent to 2.45x10-11 m) into this equation, we can find the frequency. Once we have the frequency, we can use the formula to calculate the energy of the photon in joules.



Given:
Wavelength (λ) = 2.45x10-11 m

Using the equation c = λf, where c = 3.00x108 m/s

f = c / λ = (3.00x108 m/s) / (2.45x10-11 m) = 1.22x1019 Hz



Next, we can use the formula E = hf to calculate the energy:



E = (6.626x10-34 J·s) x (1.22x1019 Hz) = 8.08x10-15 J



To express the energy numerically in kilojoules per mole, we need to convert the energy in joules to kilojoules and then divide by Avogadro's constant (6.022x1023 mol-1).



Energy per mole = (8.08x10-15 J / 1000) / (6.022x1023 mol-1) = 1.342x10-40 kJ/mol

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