Sorry I could not deliver my point. nMy point is that the colour of contour along the surface is red ( completely ) while selecting mass fraction of H20. In contrast, on selecting moles fraction 0f H20, the colour of contours is showing variation from blue to the green. by looking at contours of both, its appearing moles of h20 are changing but mass fraction 0f h20 is constant. from this, I am just thinking that mass fraction part (Contour color distribution) should be changed a little bit.nin this case, I have air & h20 mixture. nRegards,nAbbas Razan