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Homework Statement
i have a thermdyanmics process. with a constant pressure, constant volume and adiabatic. please see the attachment.
Homework Equations
from C>A (constant pressure)
so change in pressure = 0
equations needed to do this problem:
Pressure* V = n *R* T > main equation
heat = Q = Cp * n * change in temperature > main
(Cp is called the specific heat at constant pressure)
The Attempt at a Solution
our goal is use Q = Cp n * change in temperature
BUT we don't know change in temperature
we know Cp = 20.8 for an ideal monatomic gas (just a constant you look up in a physics textbook)
n = 1 mole
so how do we find change in temperature?
we need to use P Vinitial = n R Tinitial
400 * (1) = 1 * 8.315 * Tinitial
so Tinitial = 48.1058 Kelvin
P Vfinal = n R Tfinal
400 * 2 = 1 * 8.315 * Tfinal
so Tfinal = 96.2117 Kelvin
now we are done!
Q = n * Cp * change in temperature
Q = (1) *( 20.8 J/mol*K ) (96.2117  48.1058 Kelvin)
Q = 1000.6 Joules
is this right?
thank you
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