Calculating molar specific heat capacity - not a monatomic gas

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SUMMARY

The discussion focuses on calculating the molar specific heat capacity (C_p) of an ideal gas under constant pressure conditions. The user provided a scenario where 25 J of heat is added to one mole of gas, which expands from 4.97 x 10^-4 m^3 to 7.02 x 10^-4 m^3 at a pressure of 2.62 x 10^4 pascals. The calculated C_p was found to be -0.0918 J/(mole*Celsius), leading to confusion regarding the validity of a negative specific heat capacity. The user confirmed that J/(mole*C) is equivalent to J/(mole*Kelvin), eliminating unit conversion issues.

PREREQUISITES
  • Understanding of the ideal gas law
  • Familiarity with thermodynamic equations, specifically Q = C_p*n*(delta T)
  • Knowledge of unit conversions between Celsius and Kelvin
  • Basic principles of heat transfer in thermodynamics
NEXT STEPS
  • Research the implications of negative specific heat capacities in thermodynamics
  • Learn more about the ideal gas law and its applications
  • Study the derivation and application of the equation P(Delta V) = nR(Delta T)
  • Explore common mistakes in thermodynamic calculations and how to avoid them
USEFUL FOR

Students and professionals in thermodynamics, physics enthusiasts, and anyone involved in heat transfer calculations will benefit from this discussion.

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1. Suppose that 25 J of heat is added to one mole of an ideal gas. The gas expands at a constant pressure of 2.62 x 10^4 pascals while changing its volume rom 4.97 x 10^-4 m^3 to 7.02 x 10^-4 m^3. Calculate C_p and express in Joule / (mole * Celsius)

2. Relevant equations
Q = C_p*n*(delta T)
P(Delta V) = nR(Delta T)

3. Attempt at solution
25 J = C_p (1 mole) (Delta T)

Delta T = .64632 Kelvin
Delta T = -272.35 Celsius

25 J = C_p (1 mole) ( .272.35 Celsius)

C_p = -.0918 J / (mole*Celsius)

4. Question:
I inputted the answer into the online system as +.0918 J / (mole*celsius)
However, it is telling me that I am wrong.

Could there be a negative molar specific heat capacity? That doesn't make too much sense to me because shouldn't the molar specific heat raise the temperature?

Or did I do some stupid mistake with units/wrong equations?
 
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Never mind.

I see that J/mole*C is the same thing as J/mole*Kelvin
No need for a conversion.
 

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