An acid `HA` is `40%` dissociated in an aqueous solution. The hydronium ion concentration of its `0.2M` solution would be

Options

A. `0.08 M`
B. `0.4M`
C. `0.2 M`
D. None

Answer

A

Explanation

`{:(,HA+,H_(2)OhArr,H_(3)O^(o+)+,A^(Theta)),("Initial",1,0,0,0),("Final",C(1-alpha),,Calpha,Calpha):}`
`[H_(3)O^(o+)] = Calpha (alpha = (40)/(100)=0.4)`
`= 0.2 xx 0.4 (C = 0.2M)`
`= 0.08`.