How to Calculate Maximum Pressure from Combustible Gas in a Vessel?

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SUMMARY

This discussion focuses on calculating the maximum pressure produced inside a vessel when igniting a known amount of combustible gas, specifically a hydrogen/air mixture in a sealed 100ml container at 25°C. The key formula for determining pressure is derived from the ideal gas law, expressed as P = (nRT)/V, where n represents the number of moles, R is the gas constant (8.314 J/(mol·K)), and V is the volume in liters. The energy change during combustion, calculated using the heat of formation, is essential for determining the resulting temperature of the gas, which directly influences the pressure outcome.

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Hi,
I have no chemistry background and my head is swimming with heat of formation heat of combustion heat of explosion enthalpy ideal gas law and so on

What I'm trying to find out is how would I go about calculating the maximum pressure produced inside a vessel when a known amount of combustible gas was ignited?

i.e a hydrogen/air mixture inside a sealed 100ml container with a starting temperature of 25 deg C

Any examples or at least a point in the right direction is greatly appreciated.

Thank You.
 
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For the steady state end point (ie. ignoring any shockwaves etc)
You would need the number of moles of gas at the start and the end - so if you were burning a solid/liquid fuel and ending up with a gas you are goign to have more pressure at the end just because there is more gas.
Then from the energy change you have to work out what temperaure increase the resulting gas is going to have.
 
Thank You for the response,
Lets see if I understand this at all.
Hydrogen reaction with oxygen 2H2 + O2 --> 2H20
heat of formations 2H2 = 0 02 = 0 --> 2H20 2(-241.8) so the energy change is 483.6kj/mol ?
What formula(s) to I use to convert that to temperature?
once i have the temperature am I correct that
P = (number of moles * gas constant {8.314}* temp(k))/volume (100ml) and that pressure is in torr?

Thank you again.
 

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