molar heat capacity Definition and 15 Threads

Homework Statement:: I am trying to understand a formula given in our book for determining molar heat capacity of an ideal gas under different thermodynamic processes using a single formula, but it is confusing. The exact formula for different processes is in the screenshots below. Can someone...

At very high temperatures CO2 should have Cp = 15/2 R, since there are 3 translational, 2 rotational and 4 vibrational degrees of freedom. Experimental values are a bit higher than that, at least according to a figure I found on the internet. Is that correct? And what is the explanation? A...

We know that for an ideal gas the differential of the internal energy function is: dU = n Cv dT But is Cv the molar heat capacity or not?

Morning I am being stupid but cannot work out these problems: 1. Energy supplied to 2.0 moles of an ideal gas is 117J and it changes the temperature by 2.0K (at constant pressure).2. Calculate both molar heat capacities at constant P and V.3. Firstly, I divided 117J by 4 to get the energy...

Homework Statement Silver has a Fermi energy of 5.48 eV. Calculate the electron contribution to the molar heat capacity at constant volume, Cv, of Silver at 300 K. Express your result as a multiple of R. Is the value of Cv due principally to the electrons? If not, to what is it due? ans...

Homework Statement A diatomic ideal gas is heated at constant volume until its pressure is doubled. It is again heated at constant pressure until its volume is doubled. The molar heat capacity for the whole process is kR. Find the value of k. Homework Equations ans is k=19/6. p/t=constant...

Hi everyone, If you know the temperature rise of 2 moles of an ideal gas when a known amount of energy is transferred to it as heat, (hence are able to calculate cv by dU/dT); is the molar heat capacity simply half this value as it is half the number of moles?

Homework Statement The diagram shows the molar heat capacity of an ideal diatomic gas and the number of degrees of freedom at different temperatures. Explain why there are 3 discrete plateaus and why the curve is smooth and leaning between them. Homework Equations - The Attempt at a Solution...

Homework Statement An ideal gas has a molar heat capacity ##C_V## at constant volume. Find the molar heat capacity of this gas as a function of its volume ##V##, if the gas undergoes the following process: ##T=T_0e^{\alpha V}## here ##T_0## and ##\alpha## are constants.Homework Equations The...

I am doing my revision and noticed that metals all have a molar heat capacity ~25 J/mol/K = 3R. Ionic solids such as NaCl and CaF2 however have different molar heat capacities. (~51 and 72 respectively) Why is this? there is no explination that my lecturer gave and I can't find it online but...

dQ = nCvdT if volume is constant. However, n = pV/RT. What I don't understand is, why are we thinking n as constant when doing the integral? I had two problems that involved this on a test I had today. At first I kept it constant and then changed n. But then I thought, wait... isn't there a T...

Homework Statement Hi there. I'm having some trouble on solving this exercise, which you can find on Callen 2nd edition. A simple fundamental equation that exhibits some of the qualitative properties of typical crystaline solids is: u=Ae^{b(v-v_0)^2}s^{4/3}e^{s/3R} Where A,b, and v0 are...

Homework Statement Just wanted to find some clarity regarding this subject. In my textbook, it states that Q = nCvdT for constant volume and Q = nCpdT for constant pressure. However, one of the TA's in my classes were telling us how dU = nCpdT for constant pressure and dU = nCvdT for...

A monatomic ideal gas undergoes a process in which the ratio of P to V at any instant is constant and equals to 1. What is the molar heat capacity of the gas? (A) 4R/2 (B) 3R/2 (C) 5R/2 (D) 0

If I apply 200 J of energy as heat to 4 moles of an ideal gas at constant pressure and the temperature rises by 4 K, then the molar heat capacity at constant pressure will be Cp = Q / (n * deltaT) = 200 / (4 x 4) = 12.5 J K mol Am I on the right lines here?