MHTCET 15 Apr 2026 Shift 2 Paper

Concept:A strong acid like HCl ionises completely in water, so its hydrogen ion concentration equals the acid concentration. The pOH is then found using the relationship between pH and pOH at $25^\circ C$.Explanation:HCl is a strong acid, so it undergoes complete ionisation in aqueous solution.For $0.001 M$ HCl, the concentration of hydrogen ions is:$$[H^+] = 0.001 = 10^{-3} M$$Now, calculate the pH of the solution using the formula:$$pH = -\log[H^+]$$Substitute the value of $[H^+]$:$$pH = -\log(10^{-3}) = 3$$At $25^\circ C$, the ion product of water gives the relation:$$pH + pOH = 14$$Rearranging for pOH:$$pOH = 14 - pH$$Substitute the calculated pH value:$$pOH = 14 - 3 = 11$$Therefore, the pOH of the given HCl solution is 11.Answer:Option A: 11