This is an acid-base reaction (neutralization): Al(OH)3 is a base, H2SO4 is an acid.
Reactants:
, Al(OH)3
, Aluminum oxide trihydrate
, Trihydroxyaluminum 



, Sulfuric acid, concentrated (> 51% and < 100%)
, H2SO4
, Battery acid
, Hydrogen sulfate
, [SO2(OH)2] 
; Colorless to dark-brown, oily, odorless liquid. [Note: Pure compound is a solid below 51°F. Often used in an aqueous solution.] 
Products:

, Cake alum
, Aluminium sulfate (2:3)
, Aluminium sesquisulfate 
