Measurements of electron transport, effective ionization, and attachment coefficients are reported for C2F4. In addition, measurements of the electron drift velocity and the effective ionization coefficient as a function of the density-reduced electric field E/N are reported for mixtures of C2F4 with Ar. The measured effective ionization coefficients in C2F4/Ar mixtures indicates a contribution to these coefficients from Penning ionization in dilute C2F4/Ar mixtures. The rate constant for electron attachment to C2F4 as well as the product of the longitudinal electron diffusion coefficient and the gas number density NDL in mixtures of C2F4 with Ar as functions of E/N are also reported.