Question

25 ml of a solution of barium hydroxide on titration with 0.1 molar solution of hydrochlroric acid gave a titre value of 35 ml . The molarity of sodium hydroxide is ?

Answer 1

You mean the molarity of the parent `"barium hydroxide"` solution........

Explanation:

We assess the following stoichiometric equation:

`Ba(OH)_2 + 2HCl(aq) rarr BaCl_2(aq) + 2H_2O(l)`.

And thus 2 equiv acid are required to neutralize each equiv barium hydroxide.

Now, `"concentration"="moles of solute"/"volume of solution"`, i.e. `C=n/V`, there were `0.1*mol*L^-1xx0.035*L=3.5xx10^-3*mol` WITH RESPECT to hydrochloric acid.......

And, thus, by the given stoichiometry, there was an initial concentration of .......

`(3.5xx10^-3*molxx1/2)/(0.025*L)=0.070*mol*L^-1` with respect to the PARENT `Ba(OH)_2` solution. And I would like you to check on the solubilities of barium hydroxide to see if the question actually drew from experimental data.