The letter ‘Q’ is not used as the official symbol for any of the 118 named elements on the periodic table. Element symbols are always one or two letters, such as ‘O’ for Oxygen or ‘Fe’ for Iron.
The Letters Not Used
The letter ‘Q’ is one of only two letters in the English alphabet that does not appear in the symbol of any officially recognized element. The other absent letter is ‘J’. Every other letter, from ‘A’ to ‘Z’, is utilized in the one- or two-letter abbreviations representing the elements.
All 118 currently known and named elements have a unique symbol that avoids both ‘Q’ and ‘J’. Most symbols use two letters, like Gold (‘Au’) or Silver (‘Ag’), but nine elements use a single letter, such as Carbon (‘C’) and Nitrogen (‘N’).
How Element Symbols Are Chosen
The International Union of Pure and Applied Chemistry (IUPAC) regulates the assignment of element symbols and names internationally. This body sets standards to ensure scientists worldwide use a consistent and unambiguous chemical language.
Element symbols often originate from the element’s historical name, frequently drawing from Latin, Greek, or other languages used by early chemists. For example, ‘Fe’ for Iron comes from the Latin word ferrum, and ‘Au’ for Gold is derived from aurum. This reliance on non-English names explains why many symbols do not match the element’s modern English name, and why letters like ‘Q’ were bypassed.
The symbol must be a unique, one- or two-letter abbreviation derived from the accepted name, with the first letter always capitalized. This system ensures that no two elements share the same symbol, which is a requirement for clarity in chemical equations. Since ‘Q’ was not a common initial or prominent letter in the historical names of elements, it was never adopted as a permanent symbol.
The Role of ‘Q’ in Temporary Element Names
The letter ‘Q’ does appear in chemistry texts, specifically in the systematic nomenclature for superheavy elements. This temporary system is used for elements with an atomic number greater than 103 that have been recently synthesized or are yet to be officially named. The IUPAC assigns a temporary name based on the element’s atomic number.
In this temporary naming system, the number four is represented by the Latin root ‘quad,’ which includes the letter ‘q’. For instance, element 114 was temporarily named ununquadium, meaning “one-one-four.” The corresponding temporary symbol, Uuq, is always three letters long.
This three-letter symbol is a placeholder. Once the discovery is confirmed and an official name is approved, the temporary name and symbol are replaced. Element 114’s official symbol is now ‘Fl,’ confirming that ‘Q’ is not used in the final, approved element symbols.