There are several ways to express solution concentration dilute concentrated ppm molarity molality normality all of these have one thing in common they describe the

quantity of solute dissolved in a given quantity of solvent

Explanation:-

Dilute : is defined as a solution in which amount of solvent is more than the amount of solute.

Concentrated: is defined as a solution in which amount of solute is more than the amount of solvent.

ppm: ppm is defined as the concentration when 1 part of the solute is  dissolved per 1 million of the solution.

Molarity: Molarity of a solution is defined as the number of moles of solute dissolved per Liter of the solution.

Molality : Molality of a solution is defined as the number of moles of solute dissolved per kg of the solvent.

Normality: Normality of a solution is defined as the number of ram equivalents of solute dissolved per Liter of the solution.

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d.) gravity pulled particles of dust and gas together to form planets.