Question #d16b3

1 Answer
Apr 18, 2016

Answer:

Two atoms of hydrogen.

Explanation:

Sulfuric acid, #"H"_2"SO"_4#, does not contain molecular hydrogen, #"H"_2#, it only contains elemental hydrogen, #"H"#.

More specifically, one molecule of sulfuric acid will contain two atoms of hydrogen. These two hydrogen atoms will be bonded to two of the four atoms of oxygen present in the sulfate anion, #"SO"_4^(2-)#.

https://www.colourbox.com/image/sulphur-acid-molecular-structure-on-white-background-image-11888181

Molecular hydrogen has two hydrogen atoms bonded by a single covalent bond, which as you can see is not the case here.

In aqueous solution, sulfuric acid can donate two protons, #"H"^(+)#, to water, leaving behind the hydrogen sulfate anion

#"H"_ 2"SO"_ (4(aq)) -> "H"_ ((aq))^(+) + overbrace("HSO"_(4(aq))^(-))^(color(blue)("hydrogen sulfate"))#

which looks like this

http://www.chemistry.wustl.edu/~edudev/LabTutorials/PeriodicProperties/Ions/ions.html

and finally the sulfate anion

#"HSO"_ (4(aq))^(-) rightleftharpoons "H"_ ((aq))^(+) + "SO"_(4(aq))^(2-)#

which looks like this

http://www.chemistry.wustl.edu/~edudev/LabTutorials/PeriodicProperties/Ions/ions.html

So, to sum this up, sulfuric acid contains two atoms of hydrogen, not one molecule of hydrogen.