1 Yellow media without gas pocket-sugar utilization with production of acid only. 2  Red media (no change in media) -no change and no sugar utilization. 3  Pink media especially at the top, ignore gas-no sugar utilization with degradation of protein resulting in alkaline end products (this may be difficult to see).
With organic solvents with long alkane chain, such as n-hexadecane and n-decane, the water droplets become much larger and the microemulsion is unstable. In this case, solvent polarity may have become a determining factor and the long alkane chain was too hydrophobic to form a stable microemulsion with water.
What this means is that toluene will ignite with a lower amount of vapour in the air. So the upshot is that Hexane is more flammable but requires slightly more vapour in the air to ignite than does toluene. Edited to correct the flash point as the MSDS I looked for hexane quoted in Fahrenheit not Celsius. I have now converted the data.