In science, en can refer to the prefix en- (Greek) meaning "in" or "within" or or alternatively "to go into" or "cause to be", depending, as in en-ergon (work), en-tropy (entropy), or en-ergy (energy); or the abbreviation EN (technical) maning exponent E to the power of some number N.

The term EN is sometimes found as an old-fashioned short notation scheme for exponent E to the power of some number N, which is written formulaically as follows:

 \text{EN} = 10^N \,

where N is a positive number. If N equals 22, for example:

 \text{E22} = 10^{22} \,

This notation scheme is useful in expressing shorthand notation for numbers of atoms in a human molecule which can reach upwards E27, depending on atom, such as hydrogen or oxygen. Hence, for instance, the notation:

Zn_{10,000,000,000,000,000,000,000} \,

become shortened to:


or in subscript notation:

 Z_{E22} \,

or in Latex notation:

 Z_{10^{22}} \,

all of which are equivalent, which signify that there are 10 sextillion Zinc atoms in the average human molecule.

See also
‚óŹ Number of atoms in

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