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A sample of gas occupies 2.30 L at 825 mmHg and 70.0°C. What is its volume at STP

User Mpavlov
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1 Answer

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Answer:

V₂ = 2.0 Liters at STP conditions

Step-by-step explanation:

Solving problem using the combined gas law

Given:

Case I Conditions Cast II Conditions

P₁ = 825mmHg P₂ = 760mm

V₁ = 2.30 Liters V₂ = ?

T₁ = 70°C + 273 = 343K T₂ = 0°C = 273K

Substitute into combined gas law assuming moles of gas remains constant; solve for unknown volume under case 2 conditions

P₁·V₁/n₁·T₁ = P₂·V₂/n₂T₂ => V₂ = P₁·V₁·T₂ / P₂·T₁ => note: in this solution, moles of gas remains constant as is disregarded in final calculation.

V₂ = (825mm)(2.3L)(273K) / (760mm)(343K) = 1.987 Liters (calculator answer) ≅ 1.9 Liters (2 sig figs based on given volume (V₁)

V₂ = 1.987 Liters ≅ 2.0 Liters (2 sig figs based on given volume (V₁)

User Skylar Ittner
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