Introduction to Le Chatelier's Principle · 勒夏特列原理简介
| English | 中文 | Pinyin · 拼音 |
|---|---|---|
| Le Chatelier's principle/lə ˈtʃeɪtlɪəz ˈprɪnsɪpl/ | 勒夏特列原理 | lēi xià tè liè yuán lǐ |
A system that pushes back
- Disturb a balanced reaction and it fights the change.
- Add a reactant, and it consumes some of it.
- Squeeze the volume, and it shifts to relieve the pressure.
- The balance always adjusts to oppose whatever you did.
一个会反抗的系统
- 扰动一个平衡的反应,它会对抗这个改变。
- 加入一种反应物,它会消耗掉一些。
- 挤压体积,它会移动以缓解压强。
- 平衡总会调整,去对抗你所做的一切。
Shifting to counteract
- Le Chatelier's principle 勒夏特列原理 says a system at equilibrium responds to a stress.
- It shifts in the direction that partly counteracts that stress.
- The result is a new equilibrium.
移动以抵消
- 勒夏特列原理说处于平衡的系统会对扰动作出响应。
- 它朝部分抵消那个扰动的方向移动。
- 结果是一个新的平衡。
Concentration and pressure
- Add a substance and it shifts away from it; remove one and it shifts toward it.
- Increase the pressure (smaller volume) and it shifts toward fewer gas moles.
- Decrease the pressure and it shifts toward more gas moles.
浓度与压强
- 加入一种物质,它就移离那种物质;移走一种,它就移向那种。
- 增大压强(体积变小),它就移向气体摩尔数更少的一边。
- 减小压强,它就移向气体摩尔数更多的一边。
Adding more reactant to an equilibrium shifts it toward... · 向平衡体系中加入更多反应物，平衡向...移动。
The system shifts away from the added reactant, making products. · 系统移开加入的反应物一侧，生成产物。
Increasing the pressure shifts a gas equilibrium toward the side with... · 增加压力会使气体平衡向...一侧移动。
Fewer gas moles relieve the higher pressure. · 更少的气体摩尔数可缓解较高的压力。
Removing a product shifts the equilibrium ____ (toward products). · 移除产物会使平衡向____移动（朝向产物）。
The system shifts toward the side you removed from. · 系统移向您移除物质的那一侧。
Temperature shifts
- Treat heat as a reactant or a product.
- Heating an exothermic reaction shifts it backward.
- Heating an endothermic reaction shifts it forward.
温度引起的移动
- 把热当作反应物或产物。
- 加热放热反应会使它逆向移动。
- 加热吸热反应会使它正向移动。
Stress the equilibrium · 对平衡施加应力
Change temperature, pressure or a concentration and watch the equilibrium shift to oppose the change. · 改变温度、压力或浓度，观察平衡移动以抵消该变化。
Heating an exothermic reaction shifts it... · 加热放热反应会使其...
Heat is a product of an exothermic reaction, so adding heat shifts it back. · 热量是放热反应的产物，因此加入热量会使其逆向移动。
You add more reactant to a system at equilibrium. What happens?
- The system shifts forward to use up the added reactant.
- More product forms until a new balance is reached.
你向平衡系统中加入更多反应物。会发生什么?
- 系统正向移动以消耗加入的反应物。
- 更多产物形成,直到达到新的平衡。
A concentration change alters the value of $K$. · 浓度变化会改变$K$的值。
Only temperature changes $K$; concentration and pressure only shift position. · 只有温度改变$K$；浓度和压力仅改变位置。
The shift only partly counteracts the stress, reaching a new equilibrium. · 移动只能部分抵消应力，达到新的平衡。
It never fully undoes the change; it settles at a new balance. · 它永远不会完全消除变化；而是 settling 在一个新平衡点。
The system shifts to partly undo the stress, never fully -- it reaches a new equilibrium, not the old one. For pressure, only gas moles count (solids and liquids do not shift it). And only a temperature change actually changes $K$; concentration and pressure shifts leave $K$ the same.
系统移动以部分抵消扰动,绝不是完全——它达到一个新平衡,而不是旧的。对压强,只有气体摩尔数算数(固体和液体不会使它移动)。而且只有温度变化才真正改变 $K$;浓度和压强的移动让 $K$ 不变。
Le Chatelier's principle says a stressed equilibrium shifts to partly counteract the stress. Adding a substance pushes away from it; raising the pressure favours fewer gas moles; heating favours the endothermic direction. Only a temperature change alters $K$ itself.
勒夏特列原理说受扰动的平衡会移动以部分抵消扰动。加入一种物质就推离它;升高压强偏向气体摩尔数更少;加热偏向吸热方向。只有温度变化才改变 $K$ 本身。