What Is the Hydronium Ion Concentration of a 0 A)30 × 10^-2 Mol L^-1
B)4

Multiple Choice

What is the hydronium ion concentration of a 0.500 mol L^-1 acetic acid solution with K_a = 1.8 × 10^-5? The equation for the dissociation of acetic acid is below: $$\mathrm { CH } _ { 3 } \mathrm { CO } _ { 2 } \mathrm { H } ( a q ) + \mathrm { H } _ { 2 } \mathrm { O } ( l ) \rightleftharpoons \mathrm { H } _ { 3 } \mathrm { O } ^+ ( a q ) + \mathrm { CH } _ { 3 } \mathrm { CO } _ { 2 }^ - ( a q )$$

A) 3.0 × 10^-2 mol L^-1
B) 4.2 × 10^-2 mol L^-1
C) 3.0 × 10^-3 mol L^-1
D) 4.2 × 10^-3 mol L^-1