Understanding the Concepts
* Boyle's Law: For a fixed amount of gas at constant temperature, the pressure and volume are inversely proportional. This means if you decrease the volume, the pressure will increase, and vice versa.
* Combined Gas Law: This law combines Boyle's Law, Charles's Law (relating volume and temperature), and Gay-Lussac's Law (relating pressure and temperature) into a single equation:
(P₁V₁)/T₁ = (P₂V₂)/T₂
Where:
* P₁ = Initial pressure
* V₁ = Initial volume
* T₁ = Initial temperature (in Kelvin)
* P₂ = Final pressure
* V₂ = Final volume
* T₂ = Final temperature (in Kelvin)
Solving the Problem
1. Identify the knowns and unknowns:
* P₁ = 67.5 mm Hg
* V₁ = 326 mL
* V₂ = 135 mL
* T₁ = T₂ (temperature is constant)
* P₂ = ? (the pressure we want to find)
2. Since the temperature is constant, the combined gas law simplifies to Boyle's Law:
P₁V₁ = P₂V₂
3. Plug in the known values and solve for P₂:
(67.5 mm Hg) * (326 mL) = P₂ * (135 mL)
P₂ = [(67.5 mm Hg) * (326 mL)] / (135 mL)
P₂ ≈ 163.4 mm Hg
Answer: The pressure of the HCl gas in the 135-mL flask would be approximately 163.4 mm Hg.
