Question

State and explain Avogadro's law.

Answer 1

Avogadro's law:

• Amedeo Carlo Avogadro, an Italian physicist, is commemorated by Avogadro's law.
• Avogadro's law asserts that equal volumes of various gases contain an equal number of molecules under the same temperature and pressure circumstances.
• Because it connects temperature, pressure, volume, and amount of material for a particular gas, Avogadro's law is intimately connected to the ideal gas equation.
• Avogadro's law also means the ideal gas constant is the same value for all gases, so:

$$\begin{gathered} \mathrm{constant}=\frac{{\mathrm{P}}_1{\mathrm{V}}_1}{{\mathrm{T}}_1{\mathrm{n}}_1}=\frac{{\mathrm{P}}_2{\mathrm{V}}_2}{{\mathrm{T}}_2{\mathrm{n}}_2} \\ \Rightarrow \frac{{\mathrm{V}}_1}{{\mathrm{n}}_1}=\frac{{\mathrm{V}}_2}{{\mathrm{n}}_2} \\ \Rightarrow {\mathrm{V}}_1{\mathrm{n}}_2={\mathrm{V}}_2{\mathrm{n}}_1 \end{gathered}$$

• Where, ${\mathrm{V}}_1$ is the first volume, ${\mathrm{V}}_2$ is the second volume, ${\mathrm{n}}_1$ is the first amount of gas (in moles), ${\mathrm{n}}_2$ is the second amount of gas (in moles)

Example of Avogadro's law:

• The deflation of automotive tyres is another typical use of Avogadro's rule.
• The number of moles of air contained in the tyre reduces as the trapped air inside the tyre exits.
• As a result, the volume filled by the gas decreases, causing the tyre to lose form and deflate.