1 (137)

Prévia do material em texto

Chapter 7 The Quantum-Mechanical Model of the Atom 137 Atomic Spectroscopy 7.65 When the atom emits the photon of energy that was needed to raise the electron to the n = 2 level, the photon has the same energy as the energy absorbed to move the electron to the excited state. Therefore, the electron has to be in n = 1 (the ground state) following the emission of the photon. 7.67 According to the quantum-mechanical model, the higher the n level, the higher the energy. So the transition from 3p 1s would be a greater energy difference than a transition from 2p 1s. The lower-energy transition would have the longer wavelength. Therefore, the 2p 1s transition would produce a longer wavelength. 7.69 (a) Given: n = 2 n = 1 Find: Conceptual Plan: n = = Solution: = This transition would produce a wavelength in the UV region. Check: The units of the answer (m) are correct. The magnitude of the answer is reasonable because it is in the region of UV radiation. (b) Given: n = 3 = Find: Conceptual Plan: n Solution: = = m This transition would produce a wavelength in the UV region. Check: The units of the answer (m) are correct. The magnitude of the answer is reasonable because it is in the region of UV radiation. (c) Given: n = 4 = 2 Find: Conceptual Plan: = 4 Solution: This transition would produce a wavelength in the visible region. Check: The units of the answer (m) are correct. The magnitude of the answer is reasonable because it is in the region of visible light. Copyright © 2017 Pearson Education, Inc.