Respuesta :
1) Data:
T₁ = 21°C
T₂ = 51°C.
V₁ = V₂ = 15.6 L
P₁ = 249 kPa.
Pb = 269 kPa.
Questions:
• n = ?
• P₂ = ?
• Will the tires burst at the peak temperature? Explain.
• To what pressure should the tire pressure be reduced before starting the ride to avoid bursting of the tires in the desert heat? (Assume no significant change in tire volume.)
Pi = ?
2) Formula:
PV = nRT
P₁ / T₁ = P₂ / T₂
3) Solution
i) n
P₁V₁ = nRT ⇒ n = P₁V₁ / [RT₁]
n = 249 kPa × 15.6 liter / [8.314 (liter-kPa / mol-K) × (21 + 273.15K) ] =
n = 1.588 mol
ii) P₂
P₂ = P₁ T₂ / T₁ = 249 kPa (50 + 273.15 K) / (21 + 273.15K) = 273.5 kPa
iii) Tires will burst, since P₂ > Pb
iv) Pi
Pi / T₁ = Pb / T₂
Pi = Pb T₁ / T₂ = 269 kPa (21 + 273.15K) / (50 + 273.15K) = 244.9 kPa
The pressure shoul to be reduced to less than 244.9 kPa before starting to avoid the bursting of the tires in the desert heat.
T₁ = 21°C
T₂ = 51°C.
V₁ = V₂ = 15.6 L
P₁ = 249 kPa.
Pb = 269 kPa.
Questions:
• n = ?
• P₂ = ?
• Will the tires burst at the peak temperature? Explain.
• To what pressure should the tire pressure be reduced before starting the ride to avoid bursting of the tires in the desert heat? (Assume no significant change in tire volume.)
Pi = ?
2) Formula:
PV = nRT
P₁ / T₁ = P₂ / T₂
3) Solution
i) n
P₁V₁ = nRT ⇒ n = P₁V₁ / [RT₁]
n = 249 kPa × 15.6 liter / [8.314 (liter-kPa / mol-K) × (21 + 273.15K) ] =
n = 1.588 mol
ii) P₂
P₂ = P₁ T₂ / T₁ = 249 kPa (50 + 273.15 K) / (21 + 273.15K) = 273.5 kPa
iii) Tires will burst, since P₂ > Pb
iv) Pi
Pi / T₁ = Pb / T₂
Pi = Pb T₁ / T₂ = 269 kPa (21 + 273.15K) / (50 + 273.15K) = 244.9 kPa
The pressure shoul to be reduced to less than 244.9 kPa before starting to avoid the bursting of the tires in the desert heat.