MC> Go to the drug store and buy a pack of litmus paper. Test some various
 MC> liquids and record the PH. THen compare your gizmo's reading.
Sorry, litmus paper only has one color shift, turning either pink or
blue--just like hydrangeas!  There is a "universal" test paper that
is a combination of different indicators normally yellow and can give
a general indication over a range, but it isn't very accurate.
Paul Rogers
BS Chemistry
Cal State Long Beach
1967
... Lottery: a state tax on stupidity.
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