Consider a helium (He) atom that absorbs a photon of wavelength 330 nm. The change in the velocity (in cm s-1) of the He atom after the photon absorption is_____.
(Assume: Momentum is conserved when the photon is absorbed.
Use: Planck constant = 6.6 × 10-34 J s, Avogadro number = 6 × 1023 mol-1, Molar mass of He = 4 g mol-1)
(Assume: Momentum is conserved when the photon is absorbed.
Use: Planck constant = 6.6 × 10-34 J s, Avogadro number = 6 × 1023 mol-1, Molar mass of He = 4 g mol-1)
Correct Answer: 30
Solution and Explanation
Change in velocity of He-atoms = 30 cm s-1
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