Answer:
0.00126M
Explanation:
First, we need to obtain the H+ concentration. This is illustrated below:
pH = 2.9
pH = —Log [H+]
2.9 = —log [H+]
— 2.9 = Log [H+]
Anti log of —2.9 ie
[H+] = 10^—2.9
[H+] = 0.00126M
Now let us generate the dissociation equation of HCl. This is illustrated below:
HCl <==> H+ + Cl-
From the ionic equation,
Since 1 mole of H+ is produced by 1mole of HCl, this implies that 0.00126M of H+ will also be produce by 0.00126M of HCl.
Therefore the molarity of HCl is 0.00126M
