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Chemistry Forums for Students => Inorganic Chemistry Forum => Topic started by: _Cassie_ on June 01, 2005, 11:30:53 PM

Title: Percent ionization of acids: help needed
Post by: _Cassie_ on June 01, 2005, 11:30:53 PM
Hey all,

I am trying to work out the following question:

What is the percent ionization of the acid in a 0.0005M solution of acetylsalicyclic acid (aspirin) with a Ka of 3.0 by 10 to the negative 4.

Not sure if this is the way you work it out, but I worked out the [H3O+] and got an answer of 0.019535. I then substituted divided that by the original concentration of the aspirin and multiplied by 100%.

The answer I got was huge, and abviously not right... Can anybody help me?

Cassie.
Title: Re:Percent ionization of acids: help needed
Post by: AWK on June 02, 2005, 01:35:38 AM
Use unabbreviated Ostwald dilution law and solve quadratic equation
Title: Re:Percent ionization of acids: help needed
Post by: Borek on June 02, 2005, 06:25:50 AM
Not sure if this is the way you work it out, but I worked out the [H3O+] and got an answer of 0.019535.

This is obviously wrong - concentration of H+ is larger than the concentration of acid (and we are far from the area where such effect is justified by the water autoionization).