Calculate how many moles of hydrochloric acid are to be added to 2 liters of pure H2O so that the pH becomes equal to 2.0 ?

Calculate how many moles of hydrochloric acid are to be added to 2 liters of pure H2O so that the pH becomes equal to 2.0 

Dr W2021-01-31T15:21:25Z

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pH = -log[H+]
[H+] =10^(-pH) = 10^(-2.0) = 0.01 M
2 L * (0.01mol H+ / L) * (1 mol HCl / 1 mol H+) = 0.02 mol HCl

jacob s2021-01-31T14:57:50Z

molarity of HCl = no of moles/volume in L

                        = moles/2L

molarity of HCl = x/2 M

       HCl --------> H+ + Cl-

      moles/2 M     moles/2 M

     [H+] = [HCl]

     [H+] = moles/2  M

     2 = -log[moles/2]

                    moles = 0.02 

              0.02 moles of hydrochloric acid are to be added to 2 liters of pure H2O so that the pH becomes equal to 2.0