双语化学辞典Chem Lexicon
高中Senior high 气体 Gases

查理定律与盖-吕萨克定律Charles's and Gay-Lussac's laws

\[\frac{V_1}{T_1} = \frac{V_2}{T_2}\ (p\ \text{一定}), \qquad \frac{p_1}{T_1} = \frac{p_2}{T_2}\ (V\ \text{一定})\]\[\frac{V_1}{T_1} = \frac{V_2}{T_2}\ (p\ \text{const.}), \qquad \frac{p_1}{T_1} = \frac{p_2}{T_2}\ (V\ \text{const.})\]

含义Meaning

压强一定时体积与热力学温度成正比;体积一定时压强与热力学温度成正比。

At constant pressure volume is proportional to absolute temperature; at constant volume pressure is.

符号说明Symbols

符号Symbol含义 Meaning单位 Unit
\(T\)热力学温度(必须用 K)absolute temperature (must be K)K
\(V\)体积volumem³
\(p\)压强pressurePa

推导Derivation

  1. 查理(1787)和盖-吕萨克(1802)发现:每升温 1 °C,气体体积增加其 0 °C 体积的约 1/273。

    Charles (1787) and Gay-Lussac (1802): each 1 °C rise expands a gas by about 1/273 of its 0 °C volume.

    \[V = V_0\left(1 + \frac{t}{273.15}\right) = V_0\,\frac{273.15 + t}{273.15}\]
  2. 令 \(T = t + 273.15\),即 \(V \propto T\)。外推到 \(V = 0\) 得到绝对零度 −273.15 °C,这是开尔文温标的由来之一。

    With \(T = t + 273.15\), \(V \propto T\). Extrapolating to \(V = 0\) gives absolute zero, −273.15 °C — one origin of the Kelvin scale.

  3. 同理可由 \(pV = nRT\) 直接得到两种形式。

    Both forms also follow directly from \(pV = nRT\).

适用条件与局限Assumptions & limitations

  • 温度必须用开尔文;用摄氏度会得到错误结果。

    Temperatures must be in kelvin.

  • 低温下真实气体在到达 0 K 前已液化,直线外推只是理想化。

    Real gases liquefy long before 0 K; the extrapolation is idealised.