How many moles of H3O+ or OH− must you add to a liter of strong acid solution to adjust its pH from 3.58 to 4.08? Assume a negligible volume change.

Answer :

1.80 x 10^-4 moles/liter OH-

Explanation:

pH = 3.58 ; [H3O+] = 10^-3.58 = 2.63 x 10^-4 moles/liter

pH = 4.08 ; [H3O+] = 10^-4.08 = 8.32 x 10^-5 moles/liter

One needs to remove:

2.63 x 10^-4 moles/liter – 8.32 x 10^-5 = 1.80 x 10^-4 moles H3O+/liter

According to the equation: H3O+ + OH-=⇒ 2H2O

Moles/ liter of OH- needed:

1.80 x 10^-4 moles H3O+/liter x 1 mole OH-/1mole H3O+ = 1.80 x 10^-4 moles/liter OH-

heat or electricity in the atmosphere- c.