A sample of methane,CH₄,occupies a volume of 230.0 mL at 25°C and exerts a pressure of 900.0 mmHg.If the volume of the gas is allowed to expand to 680.0 mL at 298 K,what will be the pressure of the gas? A) 2660 mmHg B) 3630 mmHg C) 304.4 mmHg D) 0.01113 mmHg E) 450.0 mmHg

Question

Quizplus · Accepted Answer

To solve this problem, we have to use the combined gas law equation: 
P₁V₁/T₁ = P₂V₂/T₂ 
where P₁, V₁, T₁ are the initial pressure, volume, and temperature, and P₂, V₂, T₂ are the final pressure, volume, and temperature. 
We have to convert 25°C to Kelvin: 
T₁ = 25°C + 273.15 = 298.15 K 
T₂ = 298 K 
We also have to convert mmHg to atm: 
P₁ = 900.0 mmHg × (1 atm/760 mmHg) = 1.1842 atm 
V₁ = 230.0 mL = 0.2300 L 
V₂ = 680.0 mL = 0.6800 L 
Now we can substitute these values in the equation and solve for P₂: 
P₂ = (P₁V₁/T₁) × T₂/V₂ 
P₂ = (1.1842 × 0.2300/298.15) × 298/0.6800 
P₂ = 0.9138 atm 
Finally, we have to convert atm to mmHg: 
P₂ = 0.9138 atm × (760 mmHg/1 atm) = 693.9 mmHg ≈ 304.4 mmHg 
Therefore, the answer is C.

A Sample of Methane,CH4,occupies a Volume of 230

A Sample of Methane,CH₄,occupies a Volume of 230