Does Sulfuric acid donate both of it H+ protons?

  • Thread starter Thread starter gangsterlover
  • Start date Start date
  • Tags Tags
    Acid Protons
AI Thread Summary
Water can act as both an acid and a base, facilitating the dissociation of sulfuric acid (H2SO4) into bisulfate (HSO4-) and hydronium (H3O+). While H2SO4 can donate both protons, HSO4- is a weaker acid and tends to remain stable due to the distribution of charge across its oxygen atoms. At lower pH levels, the equilibrium shifts, resulting in equal concentrations of HSO4- and sulfate (SO42-), indicating that HSO4- has donated a proton to water. The negative charge on HSO4- does not inherently make it a base, as acidity and basicity are relative and depend on the context of the reaction. Understanding these concepts requires a grasp of dissociation equilibria and the Brønsted-Lowry theory of acids and bases.
gangsterlover
Messages
31
Reaction score
0
H2SO4 + H2O -> HSO4- + H3O+

A question by a noob.

I get the fact that water can act as an acid and as a base. The oxygen "pulls" the hydrogen+ ion away from the sulfuric acid oxygen hydrogen bond an gets one itself and becomes positively charged, therefore a hydronium.

However, I wonder does sulfuric acid donate it`s other proton as well. I see no reason why it wouldn`t I mean it would still be somewhat stable, cause the charge is quite spread out over the 3 oxygen atoms, so more stable more acidic. At least that`s how I am getting it when drawing those resonance structures. When the sulfuric acid molecule would lose both of them, I wonder wouldn`t the sulfuric acid be quite unstable then. And become a base, wouldn`t it just rip out the protons from the oxygen again, because of the size of sulfur in comparison with oxygen.

The oxygen couldn`t accept another proton, but what about another oxygen?

People please help me I am in a mess here :(
If I have stated something from ^^ above please tell me, I am still a underclass rookie.
Thanks.
 
Last edited:
Chemistry news on Phys.org
It can, but HSO4- is a much weaker acid than H2SO4.

It is all about dissociation equilibria. For example at pH=2.0 there is no H2SO4 in the solution (well, some traces), but concentrations of HSO4- and SO42- are identical (so at this particular pH half of HSO4- donated its proton to water).
 
But it tends to not do it because it is less stable than H2SO4? Because of the negative charge right?
 
But would the HS04- become somewhat basic because of the negative charge?
 
To call it somewhat basic or ''weakly acidic'' are relative terms. It doesn't describe very much. The negative charge doesn't indicate whether something is basic or not, there are just general trends which have many exceptions, but hold for a lot of cases.
 
Could you then shortly explain why acids don`t end up like bases when they give up their protons?
 
They do end up like bases in a sense, they will take back a proton if they can. This happens in many reactions
 
Back
Top