Why is entropy highest in gaseous state

There is more mixing involved, but the atoms of the gas go from being completely separated from each other to being closely packed with each other and the solvent. Thus, the entropy decreases. Since gases have so much more entropy than solids, the entropy change of this reaction is positive. One mole of a solid is produced from two moles of ions in aqueous solution.

Since solids have less entropy than solutions, the entropy change of this reaction is negative. Two moles of a gas are produced from one mole of a gas. Since the number of moles of gas has increased, the entropy change of this reaction is positive.

Carbon dioxide gas is dissolved under pressure in the soda before the can is opened. Re: Entropy of gas vs liquid vs solid Post by Ya Gao » Sat Jan 27, am When the molecules are in gas phase, there are many more possible states they can occupy compared to the possible states molecules can occupy when they are in liquid phase or solid phase.

With more possible states, the entropy will be higher. Re: Entropy of gas vs liquid vs solid Post by Brandon Fujii 1K » Sat Jan 27, pm Whenever a substance is being heated AND is not going through a phase change, the temperature of the substance average Kinetic Energy of each particle increases.

As the total kinetic energy of the particles of the substance increases, entropy increases. Therefore, because a gas has a higher temperature than that of a solid, the gas has a greater entropy. Re: Entropy of gas vs liquid vs solid Post by Wayland Leung » Sat Jan 27, pm What does it mean when there are more possible states a gas can occupy? How do you calculate entropy of vaporization?

Why does entropy increase with an increase in temperature? Why is entropy of the universe increasing? Can entropy be zero? How do free energy and entropy relate? Which state has a higher entropy — the liquid—gas equilibrium or the gaseous state? I have learned that at equilibrium the entropy is maximised.

What factor is responsible for this? Whatever one observes whether it is a liquid, a gas, or a mixture thereof is the state of maximum entropy for the particular values of the internal energy and volume the system currently has.

As OP noted, this is a consequence of the second law of thermodynamics. According to this law, a system with a fixed internal energy self-adjusts its free parameters in such a way that the entropy is maximized. The free parameter in OP's example is the fraction of molecules in the liquid or gaseous phase. When we say that the entropy of the gaseous phase is larger than that of the liquid phase, we are referring to the specific entropies i.

One may still wonder why liquid-gas coexistence is ever possible. As the gaseous phase has a higher specific entropy, why doesn't the system self-adjust to have all its molecules in the gaseous phase? Therefore, to have more molecules in the gaseous phase but stay at the same internal energy and volume, the system has to lower its temperature and raise its pressure.

This results in a decrease in the entropy, 1 which counteracts its increase that would have happened if the evaporation had taken place at constant temperature and pressure.