Data are provided for the relative rate of volatility of Isopar (R) L, CSSX solvent, and salt solution in relation to benzene. The results also include rates for mixtures of the various species and the impact of tetraphenylborate on the volatility. The results are consistent with the expected behavior in that the component with a lower boiling point volatizes faster than a component with a higher boiling point. Fick's diffusion law explained the data well and it predicted the diffusivity of Isopar (R) L (a mixture of hydrocarbons) intermediate temperatures between 35 and 70 degrees C. Inspection of the data shows the volatility of Isopar (R) L is approximately 1/10th that of the salt solution and approximately 1/100th that of benzene under comparable conditions at the temperatures studied. The results can be used to rank the relative volatility rate of these substances.