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Can anyone please help me to understand the engineering concept. this work.

1.A can containing air (ideal gas) is heated to 80°C then sealed. The can is left to cool in water at 15°C. Calculate the new pressure within the can.
How do i do this?? Please help.
Original post by alsayedhoota
1.A can containing air (ideal gas) is heated to 80°C then sealed. The can is left to cool in water at 15°C. Calculate the new pressure within the can.
How do i do this?? Please help.


Constant volume process
Ideal gas assumption PV = mRT
When we cool the air down, its pressure is decreasing.

try to figure the rest.
Reply 2
No sorry... I have not done physics and i don't understand the principles. but i do know about the Gas Law... but i'm not getting the right answer which is 83kpa. Please help me. I really need help to understand this... Thanks in advance.
Reply 3
P2 = (T2 * P1 ) / T1

T1 = 80 + 273 = 353 K

T2 = 15 + 273 = 288 K

P1 = 101.3 Kpa


P2 = (288 * 101.3) / 353 = 82.65 Kpa --> 83 Kpa
(edited 11 years ago)

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