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The pOH of an aqueous solution of 0.480 M trimethylamine (a weak base with the formula (CH3)3N) is .

User Ruffen
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1 Answer

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Answer:

Step-by-step explanation:

Kb of (CH₃)₃N is 7.4 x 10⁻⁵

initial concentration of (CH₃)₃N a is .48 M

(CH₃)₃N + H₂O = (CH₃)₃NH⁺ + OH⁻

a - x x x

x² / (a - x ) = Kb

x is far less than a so a - x can be replaced by a .

x² / a = Kb

x² = a x Kb = .48 x 7.4 x 10⁻⁵ = 3.55 x 10⁻⁵ = 35.5 x 10⁻⁶

x = 5.96 x 10⁻³

pOH = - log ( 5.96 x 10⁻³ )

= 3 - log 5.96

= 3 - .775

= 2.225

User Chirality
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