The [OH−] of a solution : 0.0052 M
Further explanation
Kb is the base ionization constant
LOH (aq) ---> L⁺ (aq) + OH⁻ (aq)
[tex]\rm Kb=\dfrac{[L][OH^-]}{[LOH]}[/tex]
Dissociation of weak base of CO₃²⁻ :
Reaction
CO₃²⁻ + H₂O⇒ HCO₃⁻ + OH⁻
use ICE method :
I : 0.15 0 0
C : x x x
E : 0.15-x x x
[tex]\tt Kb=\dfrac{[HCO_3^-][OH^-]}{[CO_3^{2-}]}\\\\1.8\times 10^{-4}=\dfrac{x^2}{0.15-x\approx 0.15}\\\\x^2=1.8\times 10^{-4}\times 0.15\\\\x=0.0052[/tex]
