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 maximum number of electrons that can occupy the second energy level (n=2)? ...
Which of following acids forms normal salts only? ...
In the diagram above, the gas produced is? ...
Which of the following is TRUE of Le Chatelier's Principle for an exothermic reaction? ...
Which of the following reaction is endothermic? ...
Ethanol can easily be produced by ...
What is the chemical symbol for Seaborgium? ...
A mixture of 0.20 mole of Ar, 0.20 mole of N2 and 0.30 mole of He exerts a total pressure of 2....