Question

pH Maan ki paribhasha likhi

Answer 1

a measurement of the level of acid or alkali in a substance.

Answer 2

In chemistry, pH 
is a logarithmic scale used to specify the acidity or basicity of an aqueous solution. It is approximately the negative of the base 10 logarithm of the molar concentration, measured in units of moles per liter, of hydrogen ions. More precisely it is the negative of the base 10 logarithm of the activity of the hydrogen ion.[1]Solutions with a pH less than 7 are acidic and solutions with a pH greater than 7 are basic.