How Is Heat Distribution Calculated in a Diatomic Ideal Gas Expansion?

[wowolala]

Homework Statement

A diatomic ideal gas expands at constant pressure. What percentage of the heat supplied to the gas is used to increase the internal energy of the gas? what percentage is used to do expansion work?

i know Q=CnT, and in the diatomic ideal gas, C_p= $$\frac{7}{2}$$ R. but i am so confused that the number of moles, n is not given, and T is also is not given, how get we start with this question...

thx. can someone help me

 

[member 553083]

explain this?Homework Equations Q=CnTC_p= \frac{7}{2} RThe Attempt at a SolutionSince the gas is expanding at constant pressure, its temperature will remain constant. This means that the heat supplied to the gas (Q) will be equal to the increase in the internal energy of the gas (C_p n T). Since the temperature is constant, all of the heat supplied will be used to increase the internal energy. Therefore, 100% of the heat supplied is used to increase the internal energy and 0% is used to do expansion work.