Question

define ppm .in what kind of solution this term is preferred and why

Answer 1

Concentration by volume of one part of a gas (or vapor), or by weight of a liquid or solid, per million parts of air or liquid. One ppm is roughly equivalent to 5 liters of material in an Olympic-size swimming pool.

Answer 2

PPM is defined as parts per million. it denotes the solid particles which are present in solution or air. It is preferred when the size of solute particles is very small and the quantity of particles are very large in number, in range of millions. it's denoted as 10^6.