Kinetic Theory of Temperature and Pressure · 温度的分子动理论
| English | 中文 | Pinyin · 拼音 |
|---|---|---|
| kinetic theory/kɪˈnetɪk ˈθɪəri/ | 分子运动论 | fēn zǐ yùn dòng lùn |
| kelvin/ˈkelvɪn/ | 开尔文 | kāi ěr wén |
Heat a gas — and you just make its particles fly faster
- Warm up a gas and nothing visible changes, yet its tiny particles start racing around faster.
- Temperature is, at heart, a measure of how fast the particles jiggle and fly.
- The gas also pushes on its container — pressure — because particles keep hitting the walls.
- The kinetic theory 分子运动论 explains both from one picture: countless particles in constant motion.
加热气体——你只是让它的粒子飞得更快
- 加热气体,表面上什么也没变,可它微小的粒子开始更快地四处飞奔。
- 温度本质上是粒子抖动和飞行有多快的量度。
- 气体还推着它的容器——压强——因为粒子不断撞击器壁。
- 分子运动论用一幅图景解释了两者:无数粒子处于不断的运动中。
A gas is mostly empty space
- A gas is a swarm of tiny particles, far apart, in constant random motion.
- They fly in straight lines until they collide with each other or the walls.
- Between collisions they barely feel any force — the space is mostly empty.
- This simple model predicts real gas behaviour remarkably well.
气体大部分是空的
- 气体是一群微小的粒子,相距很远,处于不断的随机运动中。
- 它们沿直线飞行,直到与彼此或器壁碰撞。
- 碰撞之间它们几乎感受不到任何力——空间大部分是空的。
- 这个简单的模型极好地预测了真实气体的行为。
Faster at higher temperature · 温度越高，分子运动越快
Raise the temperature and watch the particle-speed distribution shift to higher speeds. · 升高温度并观察分子速度分布向更高速率偏移。
A hotter gas has particles that move ____ on average. · 温度较高的气体，其粒子平均运动得____。
Higher temperature means more average kinetic energy, so faster particles. · 温度越高意味着平均动能越大，因此粒子运动越快。
Temperature is average kinetic energy
- Temperature is proportional to the average kinetic energy of the particles.
- Hotter gas ⇒ faster particles ⇒ more kinetic energy per particle.
- On the kelvin 开尔文 scale, doubling the temperature doubles the average kinetic energy.
- At absolute zero ($0\ \text{K}$) particle motion is at its absolute minimum.
温度就是平均动能
- 温度与粒子的平均动能成正比。
- 越热的气体 ⇒ 越快的粒子 ⇒ 每个粒子的动能越多。
- 在开尔文温标上,温度加倍,平均动能就加倍。
- 在绝对零度($0\ \text{K}$),粒子运动达到绝对最小。
In kinetic theory, the temperature of a gas is a measure of the particles': · 在分子动理论中，气体的温度是粒子____的量度：
Temperature is proportional to the average kinetic energy of the particles. · 温度与粒子的平均动能成正比。
Doubling the kelvin temperature of a gas doubles the average kinetic energy of its particles. · 将气体的开尔文温度加倍，其粒子的平均动能也会加倍。
On the kelvin scale, average kinetic energy is proportional to temperature. · 在开尔文温标上，平均动能与温度成正比。
Pressure comes from collisions
- Each particle bouncing off a wall gives it a tiny push.
- Pressure is the total force of all those collisions, spread over the wall's area.
- More particles, faster particles, or a smaller box all mean more collisions and higher pressure.
- So temperature and pressure both trace back to particle motion.
压强来自碰撞
- 每个粒子从器壁弹开时都给它一个微小的推。
- 压强是所有这些碰撞的总力,摊在器壁的面积上。
- 更多的粒子、更快的粒子,或更小的箱子,都意味着更多碰撞和更高压强。
- 所以温度和压强都追溯到粒子的运动。
What causes the pressure a gas exerts on its container? · 是什么导致了气体对其容器壁施加的压强？
Each collision with a wall gives a tiny push; together they make the pressure. · 每次撞击器壁都会产生微小的推力；累积起来便形成了压强。
Select all · 所有 ways to increase the pressure of a gas in a fixed container. · 选择所有能增加固定容器内气体压强的方法。
More or faster particles, or less space, all mean more frequent, harder collisions. Cooling lowers pressure. · 更多的或更快的粒子，或者更小的空间，都意味着更频繁、更猛烈的碰撞。冷却会降低压强。
Temperature must be measured in kelvin for the kinetic-theory relations. "Doubling the temperature doubles the average kinetic energy" is only true on the kelvin scale — never in $^\circ\text{C}$. Convert to kelvin first: $T_K = T_C + 273$.
在分子运动论的关系式中,温度必须用开尔文量度。"温度加倍则平均动能加倍"只在开尔文温标上成立——绝不在 $^\circ\text{C}$ 上。先换算成开尔文:$T_K = T_C + 273$。
Convert $27\ ^\circ\text{C}$ to kelvin (use $T_K = T_C + 273$). · 将 $27\ ^\circ\text{C}$ 转换为开尔文（使用 $T_K = T_C + 273$）。
$T_K = 27 + 273 = 300\ \text{K}$.
A sealed rigid box of gas is heated so its kelvin temperature doubles.
- The average kinetic energy of the particles also doubles.
- The particles hit the walls harder and more often, so the pressure roughly doubles too.
一个密封的刚性气体箱被加热,使其开尔文温度加倍。
- 粒子的平均动能也加倍。
- 粒子更用力、更频繁地撞击器壁,所以压强也大致加倍。
Kinetic theory models a gas as many tiny particles in constant random motion. Temperature (in kelvin) is proportional to their average kinetic energy, and pressure comes from their collisions with the walls. Hotter and more crowded both mean higher pressure.
分子运动论把气体建模为许多处于不断随机运动中的微小粒子。温度(用开尔文)与它们的平均动能成正比,压强来自它们与器壁的碰撞。越热和越拥挤都意味着更高的压强。