Why impurities decrease melting points.

Thread starter yaseen shah
Start date Mar 24, 2010
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decrease Impurities Melting Points

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SUMMARY

Impurities decrease the melting points of substances due to the disruption of the orderly crystal lattice structure. This phenomenon is explained by Raoult's Law, which states that the presence of a solute lowers the vapor pressure of the solvent, leading to a decrease in melting point. The discussion highlights that while this is a common occurrence, exceptions exist depending on the specific materials involved, as illustrated by the referenced phase diagrams.

PREREQUISITES

Understanding of Raoult's Law
Familiarity with phase diagrams
Knowledge of crystal lattice structures
Basic concepts of thermodynamics

NEXT STEPS

Research the effects of solute concentration on melting point depression
Study phase diagrams for various material systems
Explore the relationship between crystal structure and melting point
Investigate specific examples of melting point changes in different alloys

USEFUL FOR

Chemists, materials scientists, and students studying thermodynamics or material properties will benefit from this discussion.

Mar 24, 2010

yaseen shah

anyone tell me why melting points of any substance decrease when we add any other material

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Mar 24, 2010

Mapes

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They don't always; consider http://www.spaceflight.esa.int/impress/text/education/Images/Solidification/PhaseDiagrams/Phase_Diagrams_Image_001.png" , for example. Do you have a particular system in mind?

Last edited by a moderator: May 4, 2017