What if you got a letter in the mail, and you know it involves you, but since it is not addressed to you, you can’t open the envelope? Okay, you can’t help yourself, you need to take a peek. There is a way for you to peek inside without having to open the envelope with the use of a chemical called Hexanes.
Hexanes - (Chemistry) a liquid alkane existing in five isomeric forms that are found in petroleum and used as solvents, esp the isomer with a straight chain of carbon atoms (n-hexane). Formula: C6H14.
In industry, Hexanes are used in the formulation of glues for shoes, leather products, and roofing. They are also used to extract cooking oils from seeds, for cleansing and degreasing all sorts of items, and in textile manufacturing. They are a non polar solvent. What this means is that they will not bond with anything that has polar properties like water. Paper has water, so when you mix a small amount of Hexanes, they will not bond to the paper, and the paper will become transparent temporarily. Hence, now you can see through the envelope. How cool is that?!