Single drop hydrodynamic and mass transfer were examined with silica nanofluids. Different size nanoparticles with different concentrations of each were employed. The smallest size nanoparticle at the mid concentration of 0.003 wt% provides the highest enhancement. The average and maximum mass transfer enhancements of 51.8 and 78.7% were achieved. The data were nicely reproduced based on enhancement factor of diffusivity coefficient.