The pH of a 0.001 molar HCl solution in H₂O is:
(1) 1
(2) 2
(3) 3
(4) 4

To determine the pH of a 0.001 M HCl solution, follow these steps:

Step 1: Understanding pH Calculation

• HCl is a strong acid, meaning it fully dissociates in water:

• The concentration of H⁺ ions in solution is equal to the given molarity of HCl.

Step 2: Apply pH Formula

Since [H⁺] = 0.001 M = 10^{-3} M,

Final Answer:

(3) 3