Light of wavelength 200.0 nm is incident on a metal plate with a threshold wavelength of 400.0 nm. what is the energy of the incident photon in electron volts? a. 2.48 × 105 ev c. 6.20 ev b. 0.161 ev d. 3.10 ev

The energy possessed by a photon of a given wavelength is given by Planck's equation:
E = hc/λ, where E is the energy, h is the Planck's constant, c is the speed of light and λ is the wavelength of the photon. Substituting the values

E = (6.63 x 10⁻³⁴)(3 x 10⁸) / (200 x 10⁻⁹)
E = 1 x 10⁻¹⁸ Joules

Answer    "a salt" would be the best answerexplanationsalts can be defined as ionic compounds that are neither acids nor bases. nacl is an example of a salt, and its ionic.an enzyme is an organic compound which is covalently bonded, not ionically bonded.acids are generally held together by covalent bondsan element does not need any bonds to exist

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