Final answer:
The element at the beginning of a medical word is called a 'prefix,' and it is used to describe attributes such as number, location, time, or status. In chemistry, prefixes are also used in naming compounds, especially to indicate the numbers of atoms in binary compounds. Additionally, every chemical element has a symbol that serves as a shorthand in chemical notation.
Step-by-step explanation:
The term you are referring to is "prefix," which is an element located at the beginning of a medical word to indicate number, location, time, or status. In the context of chemistry, the prefix of binary compounds of two nonmetals starts with the element name of the first element, and if there is more than one atom of this element in the molecular formula, a numerical prefix is used to indicate the number of atoms. For example, the prefix 'mono-' is not used if there is only one atom of the first element.
The second element's name consists of three parts: a numerical prefix indicating the number of atoms of the element (if more than one), the stem of the element name (like 'ox' for oxygen or 'chlor' for chlorine), and the suffix '-ide'. Special rules apply when the element's name begins with a vowel; the 'a' or 'o' at the end of the prefix is often omitted (as in 'tetroxide' rather than 'tetraoxide').
Each element also has a chemical symbol, a shorthand representation usually derived from its English or Latin name. For example, 'He' for helium, 'N' for nitrogen, and 'Na' for sodium (from the Latin 'natrium').