코데인. 1.7×10^(-3) M C18H21NO3 pH 9.59 Kb calculate

코데인. 1.7×10^(-3) M C18H21NO3 pH 9.59 Kb calculate

 

 

Codeine (C18H21NO3) is derivative of morphine

that is used as an analgesic, narcotic, or antitussive.

It was once commonly used in cough syrups

but is now available only by prescription

because of its addictive properties.

If the pH of a 1.7×10^(-3) M solution of codeine is 9.59,

calculate Kb.

 

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pOH = 14 – pH

= 14 – 9.59 = 4.41

 

pOH = –log[OH^-] = 4.41

 

[OH^-] = 10^(-4.41) M

 

 

 

Kb = [NH4^+][OH^-] / [NH3] = (x) (x) / (C–x)

( 참고 https://ywpop.tistory.com/4294 )

 

Kb = [BH^+][OH^-] / [B] = (x) (x) / (C–x)

= (10^(-4.41))^2 / ((1.7×10^(-3)) – (10^(-4.41)))

= 9.1118×10^(-7)

 

 

 

답: Kb = 9.11×10^(-7)

 

 

 

 

[참고] solutions manual

[OH^-] = 10^(-4.41) = 3.9×10^(-5) M

 

Kb = (3.9×10^(-5))^2 / ((1.7×10^(-3)) – (3.9×10^(-5)))

= 9.2×10^(-7)

 

 

 

 

[키워드] 코데인 기준문서, 코데인 용액의 pH 기준문서, codeine dic