Mathematical expressions called _____________ characterize the waves that describe electron behavior.

• A. Schrödinger equations
• B. Wavefunctions
• C. Probability densities
• D. Wave numbers

Answer: (B)

In quantum mechanics, the waves that describe how an electron behaves are represented by the wavefunction, a complex-valued function that encodes the amplitude and phase of the electron’s quantum state. The wavefunction contains all the information about the system, and the probability of finding the electron in a region is given by the magnitude squared, |ψ|². The equation that tells how this wavefunction evolves in time and space is the Schrödinger equation, but the wave-like description itself is captured by the wavefunction. While de Broglie relations connect momentum to wave number and probability densities come from squaring the wavefunction, the fundamental mathematical expressions describing the electron’s waves are the wavefunctions.