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Naming Molecular Compounds

Just going over a quick review on my chemistry stuff. When naming molecular compounds, should the prefix system be used for compounds involving Hydrogen? For example, would H2I be Hydrogen Iodide, or Dihydrogen Iodide?

October 19, 2010

10 Comments • Newest first

uLtimatefx

[quote=andyhoang26]@uLtimatefx: Annoying concepts ftl [/quote]

True 'dat :O

Reply October 19, 2010
uLtimatefx

@andyhoang26: I don't mind memorizing info as long as it's not some retarded stuff that don't make sense.

Reply October 19, 2010 - edited
uLtimatefx

@andyhoang26: We talked a little about alkanes, alkenes and cycloalkanes then the bell rang

Reply October 19, 2010 - edited
uLtimatefx

@andyhoang26: I was also doing some Organic Chemistry today. We started with Hydrocarbons.

Reply October 19, 2010 - edited
uLtimatefx

@andyhoang26: Lol I was doing that in chemistry earlier today. Coincidence

Reply October 19, 2010 - edited
lilseventeen

It depends on how it's used.
If it's like HCl, it's hydro-(blah) because the Cl is...alone, for lack of better terminology.
If it's like HNO3, the hydrogen stays "silent"

Reply October 19, 2010 - edited
uLtimatefx

[quote=andyhoang26]General rule of thumb with Hydrogen: if its H + some other element/compound, it is most likely an acid.[/quote]

H + Non-metal

Reply October 19, 2010 - edited
BabysAreFood

[quote=carnagechaos]I understand something like CCl4 is Carbon Tetrachloride, or P2F5 is Diphosphorous pentaflouride. I'm just wondering if the rules also apply for compounds with Hydrogen, because I've heard you're not suppose to, but there are some exceptions. Just trying to make sure.[/quote]

If the hydrogen compound is an aqueous solution, then it should be named as an acid e.g. HCl (aq)
For acids, if the anion ends with -ide then drop the -ide and add -ic to the end. Also, add hydro- to the beginning e.g. Hydrochloric acid
if the anion ends with -ite, drop the -ite and add -ous to the end HNO2=nitrous acid
if the anion ends with -ate, drop the -ate and add -ic to the end HSO4=sulfuric acid

If the state of the compound is not (aq) then you name it like any other ionic compound.

Reply October 19, 2010 - edited
carnagechaos

[quote=MissMaylie]you use prefixes in molecular compounds
think about it; you don't need prefixes in ionic compounds because if you know the elements' valence number, you'd know the number[/quote]

I understand something like CCl4 is Carbon Tetrachloride, or P2F5 is Diphosphorous pentaflouride. I'm just wondering if the rules also apply for compounds with Hydrogen, because I've heard you're not suppose to, but there are some exceptions. Just trying to make sure.

Reply October 19, 2010 - edited
MissMaylie

you use prefixes in molecular compounds
think about it; you don't need prefixes in ionic compounds because if you know the elements' valence number, you'd know the number

Reply October 19, 2010 - edited