Which type of substance yields hydrogen ions h in an aqueous solution?

Acids dissociate in water to release a proton. The proton then combines with water to form a  hydronium ion.  

HCl, hydrochloric acid dissociates in water to release proton H⁺ and chloride ion Cl⁻

HCl → H⁺ + Cl⁻

H⁺ + H₂O → H₃O⁺

a pan containing water is placed in a positio n where it is exposed to a 10 mile per hour wind. the pan contains a uniform depth of 1.27 cm of water, is quite wide, and has a length of 2.44 m in the wind direction. the water in the pan is at a constant temperature of 15.5 °c.