The situation obtained when a perfect gas expands into a ...
The situation obtained when a perfect gas expands into a vacuum is
ΔH is positive and TΔ S is zero
ΔH is positive and T Δ S is negative
ΔH is negative and TΔ S is zero
ΔH is zero and T Δ S is positive
Correct answer is D
The definition of enthalpy change is
ΔH = ΔU + Pex(ΔV)
The enthalpy change is zero because both terms on the right are zero in free expansion of an ideal gas.
There is no external pressure in a free expansion, so P (ex) = 0. And the internal energy change, ΔU of free expansion in a closed system is zero since no inter molecular forces have to be overcome. The temperature remains constant and no heat is absorbed or released.
What is the atomic number of Carbon? ...
If a solid has a low melting point and dissolves readily in benzene, it would probably...
The scientist who stated that matter can be converted into energy is? ...
When water was added to a white anhydrous substance X, the colour changed to blue. X is ...
What is the atomic number of Thallium? ...
Which of the following trioxonitrate(V) salts would decompose on heating to form a metal? ...
Oxygen gas can be prepared by heating? ...
What is the mass (in grams) of 500 mL of ethanol? (density of ethanol = 0.789 g/mL) ...
Which of the following statements is not correct? The 4s orbital ...
Which of the following sketches is a graphical representation of Boyle's law? ...