Question

1.825 gm HCl is dissolved in 250 ml solution. What is the pH of that solution? Please answer with the explanation.

Answer 1

The first step is calculating the number of HCl moles. The molar mass of HCl is AH+ACl which is 1+35,5=36,5 g/mole. The formula for the pH is -lg[H+] where [H+] is the molar concentration of protons in the solution. To find the molar concentration we need to divide the number of moles by the volume(L).

We get the number of moles by dividing the mass given in the problem to the molar mass of the compound.1.825/36.5=0.05 moles of HCl so 0.05 moles of

H+.Molarity=n/V=0.05/0.25=0.2moles/liter.The pH is -lg0.2=2.321.