[charbel]

The autoionization of sulfuric acid can be described by the following chemical equation: H2SO4 (l) + H2SO4 (l) ⇌  H3SO4+(aq) + HSO4− (aq) At 25°C, K = 3 × 10−4.  a. Write an equilibrium constant expression for K H2SO4 that is analogous to Kw. 
 
Given that the density of H2SO4 is 1.8 g/cm3 at 25°C.  b. What is the concentration of H3SO4+ ?  c. What fraction of H2SO4 is ionized?
 can someone help me please.