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Guilherme Mazui

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What is the Difference Between Raoult Law and Dalton Law?

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The key difference between Raoult's Law and Dalton's Law lies in the substances they apply to and the properties they describe.

Raoult's Law deals with the vapor pressure of solids or liquids in a solution. It states that the vapor pressure of a solvent above a solution is equal to the vapor pressure of the pure solvent times the mole fraction of the solvent in the solution. The mathematical expression for Raoult's Law is Psolution = Xsolvent * P_solvent. This law is particularly useful in understanding the behavior of solutions and the partial pressure of vapor of a solution when changing the composition.

On the other hand, Dalton's Law deals with the partial pressure of non-reacting gases. It states that the total pressure of a mixture of non-reacting gases equals the sum of the partial pressures of each individual gas. The mathematical expression for Dalton's Law is Ptotal = PA + PB, where Ptotal is the total pressure of the gas mixture, and PA and PB are the partial pressures of each individual gas. This law is important in understanding the behavior of non-reacting gases in the same vessel.

In summary:

  • Raoult's Law applies to the vapor pressure of solids or liquids in a solution.
  • Dalton's Law applies to the partial pressure of non-reacting gases.
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  • What is the Difference Between Raoult Law and Dalton Law?
  • Comparative Table: Raoult Law vs Dalton Law

    • Comparative Table: Raoult Law vs Dalton Law

    Here is a table comparing Raoult's Law and Dalton's Law:

    Feature Raoult's Law Dalton's Law
    Focus Vapor pressure of solids or liquids in a solution Partial pressure of non-reacting gases in a mixture
    Mathematical Representation $$P\text{solution} = X\text{solvent} \times P_\text{solvent}^o$$ $$P\text{total} = \sum Pi$$
    Key Point The vapor pressure of a solvent above a solution is equal to the vapor pressure of the pure solvent multiplied by the mole fraction of the solvent in the solution The total pressure of a mixture of non-reacting gases is equal to the sum of the partial pressures of each gas in the mixture
    Developed By French chemist, François-Marie Raoult English chemist, John Dalton

    Raoult's Law deals with the vapor pressure of solids or liquids in a solution, while Dalton's Law deals with the partial pressure of non-reacting gases in a mixture.

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    Guilherme Mazui

    Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of SĂŁo Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.