What is the concentration of HCl if its pH is 3?

2 Answers
Apr 29, 2018

10^(-3) " M"

Explanation:

To find the concentration of something that dissociates into H^+ and something else from the pH, we use the formula:

10^(-pH)

So this becomes:

10^(-3) " M" quad(M stands for molar)

Apr 30, 2018

10^-3 \ "M"=0.001 \ "M"

Explanation:

The "pH" of an aqueous solution is given by the equation,

"pH"=-log[H^+]

  • [H^+] is the hydrogen ion concentration in terms of molarity

The dissociation equation for hydrochloric acid is:

HCl(aq)->H^+(aq)+Cl^(-)(aq)

So, one mole of hydrochloric acid contains one mole of hydrogen ions.

Therefore, the hydrogen ion concentration will be,

3=-log[H^+]

[H^+]=10^-3 \ "M"

=0.001 \ "M"