From: Geoff Ruth (gruth@leadershiphigh.org)
Date: Wed Sep 03 2003 - 16:18:15 PDT
Message-Id: <p05200f1abb7c26872f66@[192.168.1.20]> Date: Wed, 3 Sep 2003 16:18:15 -0700 From: Geoff Ruth <gruth@leadershiphigh.org> Subject: Re: pinhole measuring conductance
A conductivity meter is different than a voltmeter or ammeter. You
might be able to use an ohmmeter since (I think) conductivity meters
measure resistance or the lack thereof. Putting anything electrical
into a solution that's not specifically designed for it seems
sketchy, however.
I do conductivity labs at my school by using Radio Shack buzzers
hooked up to 9V batteries, with the wire leads from each end of the
circuit dangling into the solution. The volume of the buzzer matches
up really nicely with how much it conducts. It's not quantitative,
but it works really well qualitatively. If you want the lab handout,
e-mail me directly.
- Geoff
>Hi,
>I am trying to do an AP chemistry lab from Ebbing. The lab has students
>measure teh conductance of different solutions. The outcome to see that
>molecular do not conduct and ionic do, that strong and weak acids conduct
>differently, that concentration affects conductivity, and that mixtures
>conductivity is not always additive.
>
>It requires a conductance cell or conductance meter. I have voltmeters and
>ammeters. Are these the same?
>
>If a voltmeter works, how do you make it work? I have tried putting the
>electrodes in solution and measuring current (but why would there be
>current?), and I get no reading. If I measure potentials, I get numbers, but
>no consistent reading. If I add a battery, I get constant reading for
>potential, but it doesn't vary from solution to solution.
>
>Any suggestions?
>Has anyone ever done this?
>
>sally
>
>
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