Question bank — Nomenclature (IUPAC) — naming complex ions and compounds

False. In the formula the metal is written first (e.g. $[\text{Co}({\text{NH}}_3{)}_5\text{Cl}]$); in the name the ligands come first and are ordered alphabetically, so the two orderings almost never match.

False. You alphabetise by the ligand root, ignoring the multiplying prefix, so it files under "a" (ammine) — not "t" (tetra).

False. They are equal only when every ligand is neutral. In general $x_{\text{metal}}=(\text{ion charge})-\sum (\text{ligand charges})$; the ligand charges shift the two apart.

False. You still write it — nickel(0). The Roman numeral is mandatory whether the complex is +, −, or 0.

False. You always add -ate, but the Latin root is used only for certain metals (iron→ferrate, copper→cuprate, lead→plumbate...). Cobalt stays English: cobaltate, not "cobaltate-from-Latin".

False. Ammine (two m's) is coordinated ${\text{NH}}_3$; amine (one m) is an organic $-{\text{NH}}_2$ group. Different species — the double-m is a real distinction, not a typo.

False. The counter ion is a separate word, written with a space (like "sodium chloride"). The complex ion is built as one continuous word.

False. The whole point of the system is one-to-one mapping; isomers get distinct names (via prefixes like cis-/trans-, or different ligand-to-metal connectivity notation).

Yes. The complex ion is negative, so the metal takes -ate: it must be hexacyanidoferrate(II), not "iron(II)".

Yes. Ligands are alphabetised by root: "ammine" (a) precedes "chlorido" (c). Ammine must come first regardless of how many there are.

Yes. "ethylenediamine" already contains "di", so you use tris with parentheses: tris(ethylenediamine)cobalt(III) chloride. "tri" would collide and read as a different molecule.

Yes. The -ate suffix attaches to the metal name and the ligands stay in front of the metal: tetrahydroxidozincate(II). You never insert ligands between the metal root and its suffix.

Yes. "sulfato" is the ligand form (inside the sphere). As a free counter ion it is just "sulfate": tetraamminecopper(II) sulfate.

Yes. Compare roots "aqua" vs "ammine" ignoring prefixes; "ammine" (a-m) precedes "aqua" (a-q), so triammine is named first — but the reason is the root comparison, not the prefixes.

Because the prefix only counts how many there are; it carries no chemical identity. Sorting by "di/tri/tetra" would scramble names arbitrarily and break the one-name rule.

It signals at a glance that the complex ion carries a negative charge (parallels "-ate" in sulfate, nitrate). Without it, name and charge-sign would be ambiguous.

Ligand charges vary and the complex ion's charge is set by the counter ions; deriving $x_{\text{metal}}=(\text{ion charge})-\sum (\text{ligand charges})$ guarantees the correct value for any compound, even unfamiliar ones.

These four neutral ligands (${\text{H}}_2\text{O}$, ${\text{NH}}_3$, $\text{CO}$, $\text{NO}$) have special coordinated names by convention, so their bound form is unambiguous and distinct from the free molecule.

It mirrors ordinary ionic-salt naming (sodium chloride): positive part first, always — regardless of which part is the coordination sphere.

No — write it explicitly, e.g. nickel(0) in tetracarbonylnickel(0). Zero is a valid, required oxidation state in the name.

Anionic ligands ending in "-ate"/"-ite" take an "-o" ending too: sulfate→sulfato, nitrite→nitrito. The "-ide→-ido" rule is one case of the broader "anion becomes -o" pattern.

Name the cationic complex first, then the anionic complex, each as its own word — e.g. [Co(NH₃)₆][Cr(CN)₆] → hexaamminecobalt(III) hexacyanidochromate(III). Both spheres get full internal naming.

You still add -ate to the English name: e.g. chromium→chromate, zinc→zincate, cobalt→cobaltate. Latin roots are used only for the traditional handful (Fe, Cu, Pb, Ag, Sn, Au).

No elision of the prefix; you simply concatenate, giving "pentaaqua", "tetraammine" — the double vowel (aa) is kept and correct.