Hydrochloric acid, `HCl`
Sulfuric acid, `H2SO4`
In the solution of water, both of them will form ions. The chemical equation for ionization can be written as:
`HCl (aq) -> H^(+) (aq)+Cl^(-) (aq)`
`H2SO4 (aq) -> 2H^(+) (aq) + SO4^(-2) (aq)`
Interms of ions, they both produce hydronium ions which accounts for the acidity; they are both strong acids.
They differ on how many `H^(+)` ions can be produce in one mole of each acid. HCl produces one `H^(+)` while H2SO4 has 2 of them.