Nomenclature

Tags

Chem

Cegep/2

Word count

407 words

Reading time

3 minutes

Classified by compound type

+ Hard to remember elements

• Sr: strontium
• Sn: tin
• Cd: cadmium
• As: arsenic

Ionic

• Cation written first, then anion
• Monatomic anion suffixed with -ide

+ Common polyatomic ions

$\cancel{\mathrm{O}}$	$\mathrm{O}$	$\mathrm{O}{\phantom{A}}_2$	$\mathrm{O}{\phantom{A}}_3$	$\mathrm{O}{\phantom{A}}_4$	$\mathrm{O}{\phantom{A}}_7$
	$\mathrm{ClO}{\phantom{A}}^{-}$ or $\mathrm{OCl}{\phantom{A}}^{-}$ Hypochlorite	$\mathrm{ClO}{\phantom{A}}_2{\phantom{A}}^{-}$ Chlorite	$\mathrm{ClO}{\phantom{A}}_3{\phantom{A}}^{-}$ Chlorate	$\mathrm{ClO}{\phantom{A}}_4{\phantom{A}}^{-}$ Perchlorate
		$\mathrm{NO}{\phantom{A}}_2{\phantom{A}}^{-}$ Nitrite	$\mathrm{NO}{\phantom{A}}_3{\phantom{A}}^{-}$ Nitrate
			$\mathrm{SO}{\phantom{A}}_3{\phantom{A}}^{2-}$ Sulfite $\mathrm{S}{\phantom{A}}_2\mathrm{O}{\phantom{A}}_3{\phantom{A}}^{2-}$ Thiosulfate	$\mathrm{SO}{\phantom{A}}_4{\phantom{A}}^{2-}$ Sulfate
			$\mathrm{PO}{\phantom{A}}_3{\phantom{A}}^{3-}$ Phosphite	$\mathrm{PO}{\phantom{A}}_4{\phantom{A}}^{3-}$ Phosphate
			$\mathrm{CO}{\phantom{A}}_3{\phantom{A}}^{2-}$ Carbonate	$\mathrm{C}{\phantom{A}}_2\mathrm{O}{\phantom{A}}_4{\phantom{A}}^{2-}$ Oxalate
				$\mathrm{MnO}{\phantom{A}}_4{\phantom{A}}^{-}$ Permanganate
				$\mathrm{CrO}{\phantom{A}}_4{\phantom{A}}^{2-}$ Chromate	$\mathrm{Cr}{\phantom{A}}_2\mathrm{O}{\phantom{A}}_7{\phantom{A}}^{2-}$ Dichromate
$\mathrm{CN}{\phantom{A}}^{-}$ Cyanide $\mathrm{NCS}{\phantom{A}}^{-}$ or $\mathrm{SCN}{\phantom{A}}^{-}$ Thiocyanate
		$\mathrm{O}{\phantom{A}}_2{\phantom{A}}^{2-}$ Peroxide
		$\mathrm{C}{\phantom{A}}_2\mathrm{H}{\phantom{A}}_3\mathrm{O}{\phantom{A}}_2{\phantom{A}}^{-}$ Acetate

Type I

Constant metal cation charge => charge omitted

[!example]+
$\mathrm{KI}$ -> potassium iod==ide==
$\mathrm{CaS}$ -> calcium sulf==ide==
$\mathrm{Li}{\phantom{A}}_3\mathrm{N}$ -> lithium nitr==ide==
$\mathrm{K}{\phantom{A}}_2\mathrm{HPO}{\phantom{A}}_4$ -> potassium hydrogen phosphate

Type II

Variable metal cation charge => charge required as roman numeral

+ Common variable metal cations

• $\mathrm{Fe}{\phantom{A}}^{3+},\mathrm{Fe}{\phantom{A}}^{2+}$
• $\mathrm{Cu}{\phantom{A}}^{2+},\mathrm{Cu}{\phantom{A}}^{+}$
• $\mathrm{Co}{\phantom{A}}^{3+},\mathrm{Co}{\phantom{A}}^{2+}$
• $\mathrm{Sn}{\phantom{A}}^{4+},\mathrm{Sn}{\phantom{A}}^{2+}$
• $\mathrm{Pb}{\phantom{A}}^{4+},\mathrm{Pb}{\phantom{A}}^{2+}$
• $\mathrm{Hg}{\phantom{A}}^{2+},\mathrm{Hg}{\phantom{A}}_2{\phantom{A}}^{2+}$

[!example]+
$\mathrm{HgCl}{\phantom{A}}_2$ -> mercury==(II)== chloride
$\mathrm{MnO}{\phantom{A}}_2$ -> manganese==(IV)== oxide
$\mathrm{CoBr}{\phantom{A}}_2$ -> cobalt==(II)== bromide
$\mathrm{Pb}{\phantom{A}}_3\mathrm{N}{\phantom{A}}_2$ -> Lead==(II)== nitride

Covalent

• First nonmetal written first, then second nonmetal
• Second nonmetal suffixed with -ide
• Number of atoms required as prefix
  • ==Mono- not used on first nonmetal and on hydrogen halides==
  • Special case: pentoxide

[!example]+
$\mathrm{CO}{\phantom{A}}_2$ -> carbon ==di==oxide
$\mathrm{N}{\phantom{A}}_2\mathrm{O}{\phantom{A}}_5$ -> ==di==nitrogen ==pent==oxide
$\mathrm{HI}$ -> hydrogen iodide

Acid

• Solid or unknown state binary acid -> use ionic nomenclature
• Dissolved or unknown state oxyacid:
  • If the acid contains oxygen:
    • If anion ends in -ite:
      • Anion root + -ous acid
    • If anion ends in -ate:
      • Anion root + -ic acid
  • If the acid does not contain oxygen:
    • Hydro- + anion root + -ic acid

[!example]+
$\mathrm{CH}{\phantom{A}}_3\mathrm{COOH}$ -> acet==ic== acid
$\mathrm{HNO}{\phantom{A}}_2$ -> nitr==ous== acid
$\mathrm{H}{\phantom{A}}_2\mathrm{SO}{\phantom{A}}_4$ -> sulfur==ic== acid
$\mathrm{HCl}$ -> ==hydro==chlor==ic== acid
$\mathrm{H}{\phantom{A}}_3\mathrm{PO}{\phantom{A}}_4$ -> phosphor==ic== acid

Contributors

Ajitani Hifumi

Changelog

Last edited about 2 hours ago

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7a6541d-feat: feet