Question

H2X is a dibasic Acid which dissociate completed in water which one of the following is molarity of an aqueous solution of this Acid which has a ph of 1

Answer 1

Answer:- Molarity of the aqueous solution of the given dibasic acid is 0.05M.

Solution:- It's mentioned that the acid is completely dissociated. So, the dissociation equation for the acid would be as:

$H_2A(aq)\rightarrow 2H^+(aq)+A^-^2(aq)$

Let's say the molaity of the acid is X, then the molarity of $H^+$ ion would be 2X as there is 1:2 mol ratio between $H_2A$ and $H^+$ ion.

$H^+$ ion concentration could be calculated from given pH as:

$[H^+]=10^-^p^H$

Given pH is 1. Let's plug in the value in the above equation:

$[H^+]=10^-^1$

$[H^+]$ = 0.1

From the acid dissociation equation, $[H^+]$ = 2X

So, 2X = 0.1

$X=\frac{0.1}{2}$

X = 0.05

We have assumed the molarity of the acid as X. So, the molarity of the aqueous solution of the acid is 0.05M.

Answer 2

Answer:

Considering sulfuric acid (H2SO4) is a strong acid, 100% of all hydrogen ions will dissociate into solution. Strong acids/bases are pretty simple to convert from pH to molarity.

If the pH of the solution after adding H2SO4 is 1, then we would first find the concentration of hydrogen ions in solution. To do this, take 10 and raise it to the power of -pH. In this case it is 10^-1M or 0.1M. However since sulfuric acid is diprotic and dissociates completely, the actual molarity of H2SO4 in solution would be 0.1 / 2 or 0.05M.

Explanation: