On 2/5/2013 2:00 PM, Danny D. wrote:
Q: Does dilution of bleach actually affect it's stability over time?

My wife buys these Chlorox variations, so I decided to ask
Chlorox (800-292-2200 & 800-227-1860) what the percentage of
sodium hypochlorite was in their two products pictured below:
http://www2.picturepush.com/photo/a/...g/12122385.jpg

The answer came back as follows:
a. 10% NaClO (pool bleach)
b. 2.4% NaClO (Chlorox Ultimate Care Bleach, UPC 44600-01692)
c. 2.4% NaClO (Chlorox Toilet Bowl Cleaner with Bleach, UPC 44600-00938)

When I mentioned my goal of using pool bleach, diluted to those
concentrations with tap water, they forewarned that diluting bleach
lowers its stability and effectiveness. Huh?

Specifically, they said that if I diluted 10% pool bleach, the resulting
solution would only be effective as a disinfectant for 24 hours.

Q: Is that true?

Reading the labels, they list "inert ingredients", but I have to assume
that the "inert ingredient" is plain water. Isn't it?


Weaker solutions are more stable but there are other factors:

http://www.forceflow.com/hypochlorite/PioneerHypo.pdf

Tap water contains things like iron that catalyze decomposition.
You would want to use distilled or demineralized water for best stability.

Also note effect of pH. My tap water for example has pH of 6.5.