Determine the pH of a 0.35 M aqueous solution of CH₃NH₂ (methylamine). The K_b of methylamine is 4.4 × 10^-4.

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Quizplus · Accepted Answer

Methylamine is a weak base, and its pH can be calculated using the formula pH = 14 - pOH. First, calculate the pOH using the formula pOH = -log[OH⁻], where [OH⁻] is found from the equation Kb = [CH3NH3⁺][OH⁻]/[CH3NH2]. Solving for [OH⁻] gives approximately 0.0125 M, leading to a pOH of about 1.90. Thus, the pH is 14 - 1.90 = 12.10, which is closest to 12.09.

Determine the PH of a 0