At room temperature, ammonia (NH3) is a highly water-soluble, colorless, irritant gas with a unique pungent odor. Ammonia has a boiling point of -33Â°C and an ignition temperature of 650Â°C. Injury from ammonia most commonly is caused by inhalation, but it also may follow ingestion or direct contact with eyes or skin.
Guitar frets are thin strips of metal that are embedded in the neck of the guitar. They are raised up from the face of the fretboard in order to separate the neck into different semi-tonal intervals. This basically means that each fret indicates a different note. Frets are numbered just like the strings are. They are not, however, numbered by the metal pieces themselves but by the space in between the metal pieces. For instance, the first fret on the guitar is the space between the nut and the first metal piece. The fret wire is commonly made of a nickel/silver alloy, but stainless steel wire, although more expensive, produces longer lasting benefits.
A key feature of the sitar is its curved, movable frets, which allow for a wide variation of tuning; they are also raised so that the 11-16 tarbs, or sympathetic strings, can run under the frets. Among its 20-odd strings are 6 or 7 playable strings which are situated over the frets.