Properties of Light: Wave-Particle Duality, Spectrum, and Energy

What revolutionary view did early 20th-century studies reveal about light?

A relationship between light and an atom's electrons, leading to new understandings of energy, matter, and atomic structure.

What are the three primary characteristics of light as waves?

Wavelength (λ), Frequency (v), and Speed (c).

How is wavelength defined in the context of light?

The distance between corresponding points on adjacent waves, measured in meters (m).

What does frequency measure in wave properties of light?

The number of wave cycles (successive crests or troughs) that pass a given point per unit of time, measured in Hertz (Hz).

What is the speed of light in a vacuum?

3.00 x 10^8 m/s.

What is the electromagnetic spectrum?

A range of all types of electromagnetic radiation, including radio waves, microwaves, infrared light, visible light, ultraviolet light, x-rays, and gamma rays.

What is the relationship between frequency and wavelength?

They have an inverse relationship; as wavelength increases, frequency decreases.

What is the formula that relates the speed of light, wavelength, and frequency?

c = λν.

What did Max Planck and Albert Einstein contribute to our understanding of light?

They refined the understanding of light to include its particle nature, describing it as a stream of particles called photons.

How does the frequency of light relate to its energy?

As frequency increases, the energy of the wave increases, indicating a direct relationship.

What is Planck's constant (h)?

6.626 x 10^-34 J.s.

What is the formula for the energy of a photon?

EPHOTON = hν.

How can energy and wavelength be related through algebra?

By combining the equations c = λν and E = hν to show that as wavelength decreases, energy increases.

What is an emission spectrum?

A unique and distinct pattern of light emitted by atoms of a particular element when excited by energy.

What does the emission spectrum correspond to in atomic structure?

The movement of electrons between energy levels.

What is a quantum of energy?

The minimum energy required to move an electron from a lower energy level to a higher energy level.

What happens when an excited electron falls back to a lower energy level?

Light is emitted in the form of photons.

What is the ground state of an electron?

The lowest possible energy level an electron can occupy in an atom.

What principle states that the position and velocity of an electron cannot be determined simultaneously?

The Heisenberg Uncertainty Principle.

What does the Heisenberg Uncertainty Principle imply about electrons?

The exact position of an electron can never be found.

What happens to the wavelength of X-rays if their frequency increases?

The wavelength decreases.

What are emission spectra compared to in terms of identification?

They are like fingerprints that can identify the elements present in a sample of gases.