How many moles of HCl(g) must be added to 1.0 L of 2.0 M NaOH to achieve a pH of 0.00? (Neglect any volume change.)
A) 3.0 mol
B) 10. mol
C) 1.0 mol
D) 2.0 mol
E) none of these

Question

Quizplus · Accepted Answer

To achieve a pH of 0.00, the solution must be highly acidic, with a concentration of H+ ions equal to 1 M. Initially, 2.0 moles of NaOH are present, which will react with 2.0 moles of HCl to neutralize the base. An additional 1.0 mole of HCl is needed to achieve the 1 M H+ concentration in 1.0 L, totaling 3.0 moles of HCl.

How Many Moles of HCl(g) Must Be Added to 1