Is the gas monatomic or diatomic?

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The discussion centers on calculating the molar heat capacities at constant pressure (Cp,m) and constant volume (Cv,m) for an ideal gas after supplying 130 J of heat, resulting in a temperature increase of 4.00 K. The calculated Cp,m is 32.5 J/(mol·K), while Cv,m is found to be 7.558 J/(mol·K). The relationship between Cp and Cv is confirmed using the equation Cp = Cv + nR, where n is the number of moles and R is the gas constant. The participants discuss how to derive molar heat capacity values and clarify the use of the ideal gas equation. The gas is identified as likely monatomic based on the calculated heat capacities.
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Homework Statement



130 J of energy is supplied as heat to 3.00 moles of an ideal gas at constant pressure, the temperature rises by 4.00 K.

Calculate the molar heat capacity at constant pressure, CP,m and the molar heat capacity at constant volume, CV,m for the gas.

Is the gas monatomic or diatomic?


Homework Equations



Cp= Q/ T

Cp= Cv + nR

Cp,m = Cv,m +R

The Attempt at a Solution



Cp= Q/ T
= 130/ 4= 32.5

Cp= Cv + nR
32.5 = Cv +3 (8.314)

Cv= 7.558

heat capacity at constant pressure Cp = 32.5
at capacity at constant volume Cv = 7.558

how do i go from here to calculate molar heat capacity..
 
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Divide Cp by the number of moles. Generally speaking, Cp=\frac{pdv}{ndt}+Cv where Cp and Cv are molar heat capacities at constant pressure and volume.
 
Cp = nR + Cv

is nR= pdv/ ndt

what is dv/dt that u have in your formula...is the rate of change of volume...

or volume / temperautre?
 
Volume by temperature. You can use the ideal gas equation, PV=nRT, to find it under what ever conditions that are imposed on your system.
 
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