**4.1 Experimental fluid samples**

The composition of gas sample is shown in Tab-1. The composition of oil sample is shown in Tab-2. The oil sample is taken from surface separator. The average molecular weight of oil sample is 231.5 and the density is 0.8305, <sup>3</sup> *g* /*cm* .


Table 1. Components of gas samples


Table 2. Components of oil samples used in diffusion experiments
