# Do chemists refer to water as "dihydrogen monoxide"?

Is the name "Dihydrogen monoxide" actually what chemists would use to refer to $\ce{H2O}$ (assuming there was no common name, "water")?

Of course, this is all over the internet. I'm a little skeptical though because the similar chemical $\ce{H2S}$ is called "hydrogen sulfide", not "dihydrogen monosulfide".

No, it's not. The "dihydrogen monoxide" name is used as part of a hoax. In the scientific community, there are chemical names for water, and which one is used in the literature generally depends on how it interacts with something else (hydroxic acid and hydrogen hydroxide were two I heard most often in acid-base reactions).

IUPAC, the standards committee that sets standard names for chemical structures, suggests "oxidane" as a starting point for the construction of other names for chemicals that are derived from water. However, they do not suggest "oxidane" itself be used to refer to plain water.

Most chemists would use "water", even when writing scientific papers.

Like most of the other professionals answering here, I've given a couple of talks on international conferences and published some articles in peer-reviewed journals.

I have never used the terms dihydrogen monoxide or oxidane and do not intend to do so in a serious, scientific context.

Typically, one talks and writes about water, aqueous solutions and even uses a (traditional) term like brine when referring to an aqueous, saturated solution of sodium chloride.

I agree with the other answers. No serious chemist uses any word other than "water" in whatever language the chemist uses.

However, the name does appear to be following the established rules for the systematic naming of binary main group covalent compounds.

Take for example $$\ce{N2O5}$$:

1. We list the elements in order of increasing electronegativity: nitrogen oxygen
2. We convert the second element's names in "-ide": nitrogen oxide.
3. We use prefixes to indicate the number of each element. Note the the "-a-" in "penta-" goes away to make pentoxide easier to pronounce: dinitrogen pentoxide.

We need this sort of system to give us unambiguous names for binary compounds, especially when, for example, there are multiple oxides of nitrogen: $$\ce{N2O}$$, $$\ce{NO}$$, $$\ce{N2O3}$$, $$\ce{NO2}$$, $$\ce{N2O4}$$, and $$\ce{N2O5}$$.

Note that we rarely use the "mono-" prefix: $$\ce{NO2}$$ is nitrogen dioxide.

And we never use prefixes with the binary hydrides. The acidic ones are all named like ionic compounds, as are the metal hydrides, and the non-acidic ones all have common names that are used so frequently it is silly to use more complex names:

• $$\ce{NaH}$$ sodium hydride
• $$\ce{BH3}$$ borane
• $$\ce{CH4}$$ methane
• $$\ce{NH3}$$ ammonia
• $$\ce{H2O}$$ water
• $$\ce{HF}$$ hydrogen fluoride
• $$\ce{PH3}$$ phosphine
• $$\ce{H2S}$$ hydrogen sulfide
• $$\ce{HN3}$$ hydrogen azide

Water would thus be hydrogen oxide if anything.

Even though there are other possible oxides of hydrogen (or hydrides of oxygen), they have different names based on the anions:

• Depending on the context, and how one wished to look at the compound and its function in that context, one might also (still in principle, hypothetically), write HOH and call it "Hydrogen hydroxide." Mar 13 '17 at 18:42
• "Note that we rarely use the 'mono-' prefix: $\ce{NO2}$ is nitrogen dioxide." That's not quite right. The IUPAC naming rules for binary (two-element) covalent compounds specify that the mono- prefix is not used for the first element, but is for the second. Hence $\ce{CO}$ is carbon monoxide, rather than carbon oxide or monocarbon monoxide. Apr 21 at 1:35