Heat and mass transfer that occurs in liquid fuels, is a very important thing to know. It becomes an important thing to understand the basic elements of the spray droplet. Various models analogy of heat and mass transfer have been formulated to show the characteristics occurring within the system. The analogy model commonly used to obtain the value of heat transfer coefficient and mass is the analogy model Ranz W. E. and Marshall W. R. The analogy has requirements, such as the Lewis (Le) number is approximately one. The purpose of this experiment was to look at the results obtained from the analogy model of the Ranz-Marshall equation applied to pure droplets of n-Hexane and n-Heptane, which have Lewis numbers greater than one, with experimental data obtained. In this experiment, there is a change in temperature that increases with the change in diameter that tends to decrease. And for the Nusselts (Nu) and Sherwoods (Sh) numbers obtained from each liquid yield considerable deviations from the Ranz-Marshall analogy. So that Re
is considered can not represent speed. Therefore, a new, more general equation that is capable in calculating heat and mass transfer of all substances at different speeds is required.