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Chemistry Forums for Students => Analytical Chemistry Forum => Topic started by: Lozia on March 03, 2008, 07:07:11 PM

Title: Kohlrausch's law
Post by: Lozia on March 03, 2008, 07:07:11 PM
Basically what I need to know is, how do I use it? I did a titration of HCl and NiCl with NaOH. While I was titrating I was using a conductivity meter to get the conductivity. I also know the Ionic molar conductivities. How do I piece them all together? The reason I ask is I have to use it to estimate a steepness of a graph.
Title: Re: Kohlrausch's law
Post by: ARGOS++ on March 03, 2008, 07:53:40 PM
Dear Lozia;

Your Titration Graph for HCl with NaOH should look like the Example in the Attachment.

Point  A is the Start Point of your Titration and D is the “End Point”.
Point B is the “Equivalence Point” and point C tells you how much ml NaOH was required to get there.
You can do it graphically as in the picture or mathematically with the slopes you determine from the graph (or also from values).

I hope I have been of help to you, or have given you at least an idea who to do.

Good Luck!
                    ARGOS++

Title: Re: Kohlrausch's law
Post by: rhyno-of-the-port on March 12, 2008, 01:57:11 PM
but what do you do when the curve goes down, levels off and then increase? i'm stuck and the same thing and have to calculate the concentrations of both the nickel chloride and the hydrochloric acid
Title: Re: Kohlrausch's law
Post by: ARGOS++ on March 12, 2008, 03:01:30 PM
Dear Rhyno-of-the-port;

If I interpret your Question correctly you are looking for something similar to the left side (maybe mirrored).
Hints:
    “Starke”           =   “Strong”;     “Schwache”  =  “weak”;     “Säure”   = “Acid”.
    “Bestimmung”  =   “Determination”.

On the right side you see a “Precipitation” (= “Fällungs”) Titration.

Try to interpret both like it is done in the picture above!

I hope I have been of Help to you.


Good Luck!
                    ARGOS++
Title: Re: Kohlrausch's law
Post by: rhyno-of-the-port on March 13, 2008, 08:35:25 AM
Yes, that's it thank you very much i can do it now :D
Title: Re: Kohlrausch's law
Post by: ARGOS++ on March 13, 2008, 09:27:13 PM

Dear Rhyno-of-the-port;

You’re welcome!   ─   Soon again.

(Great!, if all the pictures are of help to you.)


Good Luck!
                    ARGOS++