Femto prefix

A prefix, symbolized by p, used in submultiples of units and corresponding to a value of 10 . See also Nano- Femto-... 

For example, if 1 pi of a 1 ppb solution (1 pg) is injected into a chromatograph, this will represent 10 femtomoles for a compound with a molecular weight of lOOg/mol The analyst must become accustomed to using prefixes that have seldom been used before femto- (1(T15), atto-(10-18), zepto- (10-21). Thus the zepto-mole contains only 602 molecules. These limits tend towards single atoms or molecules - the ultimate trace. 

In trace analysis, the units used for component content should be appropriate for the amount. The most proper system is to give the mass fraction (wb) of the trace component (B) in SI units with the appropriate prefix milli- (10 ), micro- (10 ), nano- (10 ), pico- femto- (10 ), or atto- (Table 1.1). The... 

Prefix peta- tera- giga- mega- milli- micro- nano- pico- femto- atto- ... 

By way of example, if IpiL of a Ippb solution (being about Ipg), is injected into a chromatograph, and if a mole of the analyte weighs 100 g, this will be 10 femtomol From this point the analyst must become familiarized with prefixes such as femto- (10 ), atto- (10 ), zepto- (10 ). Azeptomole contains only 602 molecules of a given compound. These quantities tend towards single atoms or individual molecules. The ultimate trace is almost attained. 

We shall first review the common units of weight and volume in the metric system and then describe methods of expressing results. The gram (g) is the basic unit of mass and is the unit employed most often in macro analyses. For small samples or trace constituents, chemists use smaller units. The milligram (mg) is 10 g, the microgram (/xg) is 10 g, and the nanogram (ng) is 10 g. The basic unit of volume is the liter (L). The milliliter (mL) is 10" L and is used conunonly in volumetric analysis. The microliter (/xL) is 10 L (10 mL), and the nanoliter (nL) is 10 L (1Q- mL). (Prefixes for even smaller quantities include pico for 10 and femto for 10" .)... 

Over a century later, chemical kinetics remains a field of very considerable activity and development indeed nine Nobel prizes in Chemistry have been awarded in this subject area. The most recent (1999) was to A. H. Zewail whose work revealed for the first time what actually happens at the moment in which chemical bonds in a reactant molecule break and new ones form to create products. This gives rise to a new area femtochemistry. The prefix femto (abbreviation f ) represents the factor 10 i and indicates the timescale, which is measured in femtoseconds, of the new experiments. As some measure of how short a femtosecond is, while you read these words light is taking about 2 million femtoseconds (2 x 10 fs) to travel from the page to your eye and a further 1 000 fs to pass through the lens to the retina. 

The origin of the prefix femto is the Danish word femten, meaning fifteen . Pico is derived from the Italian word piccolo, meaning small. Nano is derived from the Greek word vavoq, meaning dwarf. ... 

This term is nevertheless a little misleading as the prefix pico means 10 . The prefix nano (10 ) would be more appropriate because 0.6 pm represents 600nm, which is 600000 pm (Raven, 1998). There is also the problem of femtoplankton, considering that the prefix femto represents 10" (Lebaron and Nicolas, 2003). 

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