What is molar concentration of weak monobasic acid if dissociation constant is 5 10⁻⁸ and undergoes 0.5 % dissociation?

Step-by-step solution

aligned & Weak monobasic acid HA & t =0, CA & t , C - cx & Dissociation Constant ( K )= [ H ⁺ ] [ A ⁻ ] [ HA ] + A _ aq ⁻ & = cx cx c - cx & K = cx 1- x & x =0.5 % or 0.005=5 10⁻³ & So 1- x 1 & ~K = cx & C = k x ^2 = 5 10⁻⁸ (5 10⁻³ )^2 = 10⁻² 5 & =0.002 M aligned