An ideal gas undergoes an isothermal process from some initial state \(i\) to the final state \(𝑓\).
(a)
\(dU = 0 \)
(b)
\(dQ = 0\)
(c)
\(dQ = dU \)
(d)
\(dQ = dW\)
Choose the correct alternatives:
1.
(a), (b), (c)
2.
(a), (d)
3.
(b), (c), (d)
4.
(a), (c), (d)
(1, 4) Hint: In isothermal processes, the change in temperature is equal to zero.
Step 1: Find the change in the internal energy of the gas.
For an isothermal process change in temperature of the system, T =0 T =constant.
We know that for an ideal gas, dU = change in internal energy = nT = 0
[where n is the number of moles and C is the specific heat capacity at constant volume]
Step 2: Use the first law of thermodynamics.
From the first law of thermodynamics,