Light is an electromagnetic wave (Figure 5.5a of Cosmic Perspective)

Wavelength is inversely proportional to frequency (Figure 5.6 of Cosmic Perspective)

The electromagnetic spectrum (Figure 5.7 of Cosmic Perspective)

An atom consists of a nucleus surrounded by a cloud of electrons (Figure 5.8 of Cosmic Perspective)

Different atoms have different numbers of protons in their nuclei (Figure 5.9 of Cosmic Perspective)

Different isotopes of the same atom have different numbers of neutrons in their nuclei (Figure 5.9 of Cosmic Perspective)

Electron clouds in Hydrogen

Thermal, emission, and absorption spectra (Figure 5.14 of Cosmic Perspective)

Wien's law: The peak wavelength of a thermal spectrum is inversely proportional to temperature (Figure 5.19 of Cosmic Perspective)

Phases of water (Figure 5.10 of Cosmic Perspective)

Doppler effect