What is the [H₃O⁺] of a 0.14 M solution of NH₄Cl in H₂O at 25°C? (K_b for NH₃ = 1.8 × 10^-⁵) A) 1.1 × 10^-9 M B) 8.8^-6 M C) 2.5^-6 M D) 7.8^-9 M E) 1.6^-3 M

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The question asks for the pH of a 0.14 M solution of NH4Cl in H2O at 25°C. NH4Cl is a salt that dissociates in water to form NH4+ and Cl-. NH4+ (ammonium ion) is a weak acid that partially dissociates in water to form H+ and NH3. The pH can be calculated using the formula for the dissociation of a weak acid, pH = -log[H+], where [H+] is the concentration of hydrogen ions in the solution. Given the Kb (base dissociation constant) for NH3 is 1.8 × 10^-5, we can find the Ka (acid dissociation constant) for NH4+ using the relation Kw = Ka * Kb, where Kw is the ion product of water (1.0 × 10^-14 at 25°C). The concentration of NH4+ (0.14 M) and the calculated Ka value can then be used to find the [H+] concentration, and subsequently, the pH. The correct answer involves calculating these values accurately, leading to the conclusion that the pH corresponds to the concentration of H+ ions closest to the value calculated, which is option B, indicating a pH that corresponds to an [H+] of 8.8 × 10^-6 M.

​What Is the [H3O+] of a 0

What Is the [H₃O⁺] of a 0