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Topic: neutralizing weak acids  (Read 3502 times)

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Offline Julie Smith

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neutralizing weak acids
« on: October 31, 2008, 12:11:37 AM »
hi, I'm stuck on this problem hopefully someone can help.

question:

calculate the volume of 0.10M NaOH required to neutralize 10mL of 0.10M acetic acid(CH3COOH)

My attempt:

CH3COOH --> H+ + CH3COO
     0.10M         0          0         (initial [  ])
     -x               x          x          (change in [  ])
----------------------------------------------------
  0.10-x            x         x           (equivalence)

ka = 0.000018

therefore, (x)(x)/0.10(assume x is small so I ignored it)=0.000018

x= 0.00134164 =[H+]

therefore, (0.00134164M H+)(0.01L H+)/(0.10M NaOH)=0.000134164L

that number just seems way too small to me but i don't know.

thanks to anyone who can help

Offline AWK

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Re: neutralizing weak acids
« Reply #1 on: October 31, 2008, 02:17:30 AM »
THis is not an equilibrium problem, but a simple stoichiometry.
Write down a balanced neutralization reaction first.
AWK

Offline Julie Smith

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Re: neutralizing weak acids
« Reply #2 on: October 31, 2008, 03:57:47 AM »
oh ok so would it just be the formula N1V1=N2V2

so (0.1M acetic acid)(10mL acetic acid)/(0.1M NaOH)=10mL NaOH?

Offline AWK

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Re: neutralizing weak acids
« Reply #3 on: October 31, 2008, 04:58:01 AM »
Result is OK, but you can use this formula after finding the stoichiometry of acetic acid to NaOH is 1:1
AWK

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