pH is a scale used to specify the acidity or basicity of an aqueous solution. Acidic solutions are measured to have lower pH values than basic or alkaline solutions.
pH is the quantitative measure of the acidity or basicity of aqueous or other liquid solutions.
Indicators may be used to measure pH, by making use of the fact that their color changes with pH. Visual comparison of the color of a test solution with a standard color chart provides a means to measure pH accurate to the nearest whole number.
Universal indicator consists of a mixture of indicators such that there is a continuous color change from about pH 2 to pH 10.
