Chemistry Chapter 4 Review: Electron Arrangement

Questions and Answers

In what way does the photoelectric effect support the particle theory of light?

In order for an electron to be ejected from a metal surface, the electron must be struck by a single photon with at least the minimum energy needed to knock the electron loose.

What is the difference between the ground state and the excited state of an atom?

The ground state is the lowest energy state of the atom. When the atom absorbs energy, it can move to a higher energy state, or excited state.

Under what circumstances can an atom emit a photon?

A photon is emitted when an atom moves from an excited state to its ground state or to a lower-energy excited state.

How can the energy levels of the atom be determined by measuring the light emitted from an atom?

When an atom loses energy, it falls from a higher energy state to a lower energy state. The frequency of the emitted light, observed in an element's line-emission spectrum, may be measured. The energy of each transition is calculated using the equation E = hv. Signup and view all the answers

Why does electromagnetic radiation in the ultraviolet region represent a larger energy transition than does radiation in the infrared region?

Energy is proportional to frequency, and ultraviolet radiation has a higher frequency than infrared radiation. To produce ultraviolet radiation, electrons must drop to lower energy levels than they do to produce infrared radiation. Signup and view all the answers

Which of the waves shown below has the higher frequency? (The scale is the same for each drawing.) Explain your answer.

Wave B has the higher frequency. Wavelength is inversely proportional to frequency, so as the wavelength decreases, its frequency increases. Signup and view all the answers

How many different photons were emitted when excited helium atoms fall back to their ground state?

Six different photons were emitted. Signup and view all the answers

What is the frequency of the emitted light for one of the transitions?

9.7 x 10^14 Hz Signup and view all the answers

What is the wavelength of the photon emitted during an electronic transition?

9.4 x 10^9 m Signup and view all the answers

Study Notes

Photoelectric Effect

Supports the particle theory of light; electrons are ejected from metal surfaces only when struck by a single photon of sufficient energy.

Ground State vs Excited State

Ground state: lowest energy configuration of an atom.
Excited state: higher energy state attained through energy absorption.

Photon Emission

Atoms emit photons when transitioning from an excited state to the ground state or to a lower energy excited state.

Determining Energy Levels

Energy loss during transitions results in photon emission; frequency recorded in an element's line-emission spectrum.
Energy can be calculated using E = hv, indicating energy levels of the atom for each element.

Electromagnetic Radiation

Ultraviolet radiation signifies larger energy transitions compared to infrared radiation due to its higher frequency and corresponding energy levels.

Wave Frequency

Wavelength and frequency are inversely related; shorter wavelengths equate to higher frequencies.
Wave B demonstrates a higher frequency when compared to another wave.

Helium Emission Spectrum

Six distinct photons are emitted when an excited helium atom returns to its ground or lower energy states, indicated by six lines in the line-emission spectrum.

Energy and Frequency

A frequency of 9.7 x 10^14 Hz corresponds to a certain energy level transition of an atom.

Wavelength Measurement

A wavelength of 9.4 x 10^9 m indicates a specific energy transition within the electromagnetic spectrum.

Description

Test your knowledge on the arrangement of electrons in atoms with these essential flashcards. Explore concepts such as the photoelectric effect and the differences between ground and excited states of atoms. Perfect for anyone studying chemistry.