Ph is a scale used to measure weather  the chemical is acid or a base
to measure ph of a chemical  we use indicators like ph paper  etc

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but u dont got my question it that "the highest reading of pH of a chemical ?????" ok but thankzz....
or the answere is 1
and the lowest is 14
The pH value of a chemical determines whether a chemical mixture is acidic, basic or neutral in nature.Any value greater than 7 makes the solution basic and less than 7 makes it acidic.Anything=7 is neutral.
Eg:pH of Blood is 7.4(so it is basic)
pH of Water is 7 ( so it is neutral)
The highest possible pH of a chemical is 14.
The pH scale ranges from 1 to 14.
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