If the concentration of a sample of aqueous hydrosulfuric acid is 0.050 mol/L , then the hydronium ion concentration
can be calculated using the balanced equation for the dissociation of hydrosulfuric acid in water:
H2S(aq) + H2O(l) -> H3O+(aq) + HS-(aq)
Since hydrosulfuric acid is a strong acid, it fully dissociates in water, and thus the concentration of hydronium ions is equal to the concentration of hydrosulfuric acid. Therefore, the hydronium ion concentration would also be 0.050 mol/L.