What is the Difference Between Triple Point and Eutectic Point

Thekey difference between triple point and eutectic point是在三个点上，一个物质的三个阶段存在于平衡状态，而在共晶角度，特定的共晶混合物冻结或熔体。

Changing the temperature and pressure of achemical systemcan change the physical state or phase of that system because the components in that system have particularmelting and boiling pointsat which the phase changes take place between solid, liquid, and gas phases.

内容

1.Overview and Key Difference
2.What is Triple Point
3.What is Eutectic Point
4.Triple Point vs Eutectic Point Diagram
5.摘要 - 三点与共晶

什么是三点？

三重点是特定物质的固体，液体和蒸气相的温度和压力，并存。它描述了特定的热力学状态。有时，当存在时，三重点可能涉及多个固相多晶型物of the substance exist. In a相图，三重点是所有三个边界线相遇的点。

什么是共音点？

Eutectic point is the temperature and pressure at which a certain liquid mixture transforms into two solid phases at the same time upon cooling the liquid. A eutectic system is a homogenous mixture of substances that can melt or solidify at a temperature that is lower than the melting point of the constituents in that mixture. Moreover, the term eutectic temperature describes the lowest possible melting temperature for all possible mixing ratios that are involved in the formation of the mixture.

Upon heating a eutectic mixture, the lattice of one component in the mixture will melt first at the eutectic temperature. However, upon cooling the eutectic system, each component in the mixture tends to solidify, forming the lattice of that component at a distinct temperature. Solidification happens until all materials become solids. In general, a eutectic system contains two components: thus, at eutectic temperature, the liquid transforms into two solid phases at the same time and at the same temperature. Thus, we can name this type of reaction as a three-phase reaction. This is a specific type of phase reaction; for example, a liquid solidifies, forming alpha and beta solid lattices. Here, the liquid phase and solid phase are in equilibrium with each other, a thermal equilibrium.

三重点和共晶点有什么区别？

三重点是特定物质的固体，液体和蒸气相的温度和压力，并存。The term Eutectic point is the temperature and pressure at which a certain liquid mixture transforms into two solid phases at the same time upon cooling the liquid. The key difference between triple point and eutectic point is that at the triple point, three phases of a substance exist in equilibrium, whereas at the eutectic point, a particular eutectic mixture freezes or melts. In other words, at the triple point, three phases co-exist at the same temperature and pressure conditions, whereas at the eutectic point, a liquid converts into two solid phases at the same temperature and pressure conditions.

The below infographic lists the differences between triple point and eutectic point in tabular form for side by side comparison

摘要 - 三点与共晶

In brief, the triple point is the temperature and pressure at which solid, liquid, and vapour phases of a particular substance co-exist in equilibrium, while the eutectic point is the temperature and pressure at which a certain liquid mixture transforms into two solid phases at the same time upon cooling the liquid. The key difference between triple point and eutectic point is that at the triple point, three phases of a substance exist in equilibrium, whereas at the eutectic point, a particular eutectic mixture freezes or melts.

Reference:

1. Connor, Nick. “What Is Triple Point of Water – Definition.”热工程, 3 June 2019.

Image Courtesy:

1.“”Phase-diag2” By Matthieumarechal(CC BY-SA 3.0)via Commons Wikimedia
2. “共晶系统相图” By Eutektikum_new.svg: *Eutektikum.gif: Dr. Báder Imrederivative work: Michbich (talk)derivative work: Wizard191 (talk) – Eutektikum_new.svg(CC BY-SA 3.0)via Commons Wikimedia