# What is the molarity of 0.60N $H_3PO_4$ (a tribasic acid)in the following reaction?$H_3PO_4+2OH^-\rightarrow HPO_4^{2-}+2H_2O$

$\begin{array}{1 1}(a)\;0.30M\\(b)\;0.40M\\(c)\;0.90M\\(d)\;0.15M\end{array}$

Molarity=$\large\frac{\text{normality}}{\text{basicity}}$
Normality is given as 0.6N and Basicity can be inferred to be 2, hence the Molarity $= \large\frac{0.60}{2}$$= 0.3\;M$
edited Jul 17, 2014