Question

What is the pH of 0.365% (w/V) HCl aqueous solution? (HCl=36.5 u), (log 0.365=−0.4377)

• A. 1.301
• B. 1.0
• C. 2.699
• D. 0.4377

Hint:

w/V to M: (g/100 mL) × 10 / MM for M. Strong acids: pH = -log M. Ignore distractor logs. Assume dilute for activity ≈ concentration.

Answer 1

The Correct Option is B

1. w/V % = 0.365 g HCl per 100 mL solution.
2. Concentration = 0.365 g / 0.1 L = 3.65 g/L.
3. Molarity M = 3.65 / 36.5 = 0.1 M.
4. HCl is strong acid, fully dissociates: [H$^+$] = 0.1 M.
5. pH = -log [H$^+$] = -log 0.1 = 1.0.
6. Given log 0.365 not needed; perhaps distractor. Therefore, the correct option is (2) 1.0.