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Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: KraigH on December 01, 2005, 11:16:19 AM

Title: Salt Water Indicator
Post by: KraigH on December 01, 2005, 11:16:19 AM
I am looking for the solution that will detect the presence of salt water.  I have seen a dropper of soluition placed on a surface exposed to salt water and it turned red/pink when sodium chloride was present.

I initially thought the solution was Silver Nitrate but this creates a white precipitate when introducted to Chloride.

Title: Re:Salt Water Indicator
Post by: jdurg on December 01, 2005, 12:55:42 PM
A rhodium salt would do that as rhodium chloride is an intensely red color.  (Which is how rhodium got its name).  However, at about $3,000 per OUNCE of Rhodium, it would be a needlessly expensive test when something as simply as a silver nitrate solution would be just as effective.
Title: Re:Salt Water Indicator
Post by: KraigH on December 02, 2005, 12:03:38 AM
any idea what the solution was that I saw used?
Title: Re:Salt Water Indicator
Post by: jdurg on December 05, 2005, 03:50:24 PM
It could very well have been an aqueous solution of a rhodium salt.  Something like rhodium nitrate or whatnot.