pH and Applications of pH

Mention any four applications of pH

Most economical and effective method of control of soil pH is application of

Which is more acidic: a solution of pH=2 or a solution of pH=6?

The pH of solution obtained by mixing equal volumes of two aqueous solutions of pH 5 and pH 3 of the same substance is

An acid solution of pH =6 is diluted 100 times. The pH of solution becomes

An acid solution of pH=6 is diluted 1000 times, the pH of the final solution is