Silver Chloride Cell - Corrosion Meter

[duncan_ellison]

Hi all,

I'm trying to make a self contained corrosion meter.

I've acquired the necessary silver chloride cell from a lab test house (see pic below), but I cant get my head around how it is going to work. Not the process of measuring the voltages, but the actual half cell.

The silver (chloride) wire comes inside a glass vial with a porous end plug. The vial is filled with saturated Potassium Chloride.

I guess that the seawater will couple electrically with the solution in the vial, but I can't see what the purpose of this Potassium Chloride solution is.

Is it simply to buffer the electrode against the nasty solutions it might be placed in?

Won't the fact that it's Potassium rather than Sodium Chloride affect the potential difference?

Or did I just get the wrong type of reference cell?

I used to understand this stuff, but it's been too long since my college days.

Any chemistry guru's out there enlighten me?

[coopec43]

Sorry!



I can't help you but maybe something here?



DIY underwater corrosion meter...zinc reference cell? silver?...?


https://www.eng-tips.com/viewthread.cfm?qid=256352


Home made silver/silver chloride half cell

http://www.cruisersforum.com/forums/f55/home-made-silver-silver-chloride-half-cell-192161.html



F]INSTRUCTIONS FOR SALTY DOGGSTM SILVER-SILVER ...

http://www.shop.saltydoggs.com/media/Saltydoggs-Reference-Electrode.pdf