This code was widely used in the 1970s, but is much less used today. (The terms bandana code, hanky code, or flagging are much more widely used among those in the leather subculture than the term handkerchief code.) It should be noted that this code has come into more general usage today.
Generally speaking, solid turns to a liquid at its melting point. Ice turns to water at 0 degrees Celsius. Chocolate melts at 25 degrees Celsius- Yum! Ice (solid) thaws when the temperature rises above 32 degrees Fahrenheit, becoming water (liquid). Other solids (oddly) vary. Generally speaking, solid turns to a liquid at its melting point. Chocolate melts at 25 degrees Celsius- Yum! Ice (solid) thaws when the temperature rises above 32 degrees Fahrenheit, becoming water (liquid).
Thicker, oil-like stuff at room temperature with some thinner ones, and also aromatics that are gaseous at room temperature. So by freezing, you mean, when does it turn solid? The heavier hydrocarbons will start to solidify sooner than the aromatics. The flash point of gasoline is about -97F, meaning that it will still burn at 97 degrees below zero. Most labs won't even have the ability to chill a sample down that far to find out! Even the -97F mark is going to vary, based on the additives in the sample.