Gas Laws and Ideal Gas Equation Notes

## Gas Laws - **Boyle’s Law** (constant $T$ and $n$): $p*1V*1 = p*2V*2$ - **Charles’s Law** (constant $p$ and $n$): $\frac{V*1}{T*1} = \frac{V*2}{T*2}$- Implication: Absolute minimum temperature exists. - **Avogadro’s Law** (constant $T$ and $p$): $V \propto n$ ## Absolute Temperature - Kelvin scale: $Temp \space in \space °C + 273.15 = Temp \space in \space K$ ## Ideal Gas Equation - Combination of gas laws: $pV = nRT$- $R$ (Ideal Gas Constant) = $8.314 \space L \cdot kPa \cdot K^{-1} \cdot mol^{-1}$ ## General Gas Equation - When the number of moles is constant:
$\frac{p*1V*1}{T*1} = \frac{p*2V*2}{T*2}$ ## Density of Gases - Density (d) = $\frac{m}{V}$ - Density of a gas is proportional to its molecular mass (M). - Using the Ideal Gas Equation:
$d = \frac{m}{V} = \frac{pM}{RT}$ - Dry air: - Average M = $29 \space g \cdot mol^{-1}$ - Density ≈ $1.2 \space g \cdot L^{-1}$ - Gases with higher M than 29 (e.g., $CO*2$, $SO*2$) sink. - Gases with lower M than 29 (e.g., $H*2$, $He$, $CO$, $NH*3$) rise.