 
Hydrofluoric acid is a colourless highly corrosive solution of hydrogen fluoride in water. The molecule for hydrofluoric acid is HF, which is made up of one hydrogen atom and one fluorine atom. It's a weak acid, but it can be fatal if not treated properly. It has a pH of between 0.5 and 1 for concentrated solutions.
HF has a strong, irritating odour. It can be a colourless gas or a fuming liquid. It's non-flammable, but can be absorbed through the skin quickly. 
Hydrofluoric acid is used in the manufacture of silicon semiconductor chips. It is also used in commercial automotive cleaners, rust removers, and water spot removers. It may also be
used as an acid catalyst in oil refineries. Hydrofluoric acid is also commonly used to etch ceramic dental restorations to improve bonding. For similar reasons, dilute hydrofluoric acid is used to etch glass, polish glass, and frost glass. It is a component of household rust stain remover, in car washes in 'wheel cleaner' compounds, in ceramic and fabric rust inhibitors, and in water spot removers. Because of its high reactivity with glass, hydrofluoric acid is stored in fluorinated plastic containers. The principal use of hydrofluoric acid is in organofluorine chemistry. Many organofluorine compounds are prepared using HF as the fluorine source, including Teflon, fluoropolymers, fluorocarbons, and refrigerants such as freon. [Such uses have been reexamined in recent decades, and even discontinued in some cases, as fluorocarbons have been shown to worse the Greenhouse Effect that contributes to climate change. As well, fluorocarbons don't break down, and can accumulate in the environment and in the bodies of humans and animals]. |