Why are the elements from 113 named with 'unun' as the prefix?

Answer 1

The elements ununtrium, ununquadium, ununpentium, etc. are elements that have been discovered, but so far have not received a trivial name yet. There is a system for naming them temporarily.

UN meaning ONE, BI meaning TWO, TRI meaning THREE, QUAD meaning FOUR,

PENT meaning FIVE, HEX meaning SIX, SEPT meaning SEVEN, OCT meaning EIGHT,

NIN meaning NINE.

The Periodic Number is representative of the temporary name given to the element. Therefore: UNUNOCTIUM is the name for element number 118.

Direct Temporary naming rule:

The temporary names are derived systematically from the element's atomic number. Each digit is translated to a 'numerical root', according to the table to the right. The roots are concatenated, and the name is completed with the ending -ium. Some of the roots are Latin and others are Greek; the reason is to avoid two digits starting with the same letter. There are two elision rules designed to prevent odd-looking names.

• If bi or tri is followed by the ending ium(i.e. the last digit is 2 or 3), the result is '-bium' or -'trium', not '-biium' or '-triium'.
• If enn is followed by nil (i.e. the sequence -90- occurs), the result is '-ennil-', not '-ennnil-'.

The systematic symbol is formed by taking the first letter of each root, converting the first to a capital.

The suffix -ium overrides traditional chemical suffix rules, thus 117 and 118 are ununseptium and ununoctium, not ununseptine and ununocton.

All elements up to atomic number 112 have received individual permanent names and symbols, so the systematic names and symbols are only used for elements 113 and above. The systematic names are exactly those with 3-letter symbols.

Examples:Element 119:

Element 123:

Element 208: un + un + enn + ium =

un + bi + tr + ium =

bi + nil + oct + ium =ununennium (Uue)

unbitrium (Ubt)

biniloctium (Bno)Note: These examples show conjectured elements. As of 2010, Ununoctium, element 118, is the highest-numbered element discovered.