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Ch.5 - Periodicity & Electronic Structure of Atoms
McMurry - Chemistry 8th Edition
McMurry8th EditionChemistryISBN: 9781292336145당신이 사용하는 게 아니라요?교과서 변경
모든 교과서McMurry 8th EditionCh.5 - Periodicity & Electronic Structure of Atoms문제 136a
5장, 문제 136a

A minimum energy of 7.21⨉10-19 J is required to produce the photoelectric effect in chromium metal. (a) What is the minimum frequency of light needed to remove an electron from chromium?

검증된 단계별 안내
1
Identify the equation that relates the energy of a photon to its frequency. The equation is given by Planck's equation: E = h \(\nu\), where E is the energy of the photon, h is Planck's constant (6.626 x 10^{-34} J\(\cdot\) s), and \(\nu\) is the frequency of the photon.
Rearrange the equation to solve for the frequency (\(\nu\)). The rearranged equation is \(\nu\) = \(\frac{E}{h}\).
Substitute the given energy value (7.21 x 10^{-19} J) into the rearranged equation.
Perform the division to calculate the frequency. Ensure that the units of Planck's constant (Joule seconds) are correctly aligned with the units of energy (Joules) so that they cancel out appropriately, leaving the frequency in units of s^{-1}, which is also known as Hertz (Hz).
Interpret the result as the minimum frequency of light required to eject an electron from chromium, thus causing the photoelectric effect.

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주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Photoelectric Effect

The photoelectric effect refers to the phenomenon where electrons are emitted from a material when it absorbs light of sufficient energy. This effect demonstrates the particle nature of light, where photons, the light particles, must have enough energy to overcome the work function of the material to release electrons.
추천 영상:
가이드 코스
02:31
Photoelectric Effect

Energy-Frequency Relationship

The energy of a photon is directly related to its frequency through the equation E = hν, where E is energy, h is Planck's constant (6.626 × 10^-34 J·s), and ν (nu) is the frequency of the light. This relationship allows us to calculate the minimum frequency required to achieve a specific energy threshold, such as that needed for the photoelectric effect.
추천 영상:
가이드 코스
00:31
Frequency-Wavelength Relationship

Work Function

The work function is the minimum energy required to remove an electron from the surface of a material. It is a characteristic property of each material and is crucial in determining the threshold frequency of light needed to initiate the photoelectric effect. For chromium, this value is given as 7.21 × 10^-19 J.
추천 영상:
가이드 코스
01:52
Work Function Calculation Example
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교과서 질문
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In the Bohr model of atomic structure, electrons are constrained to orbit a nucleus at specific distances, given by the equation

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