Gases have just translational energy or all three forms? BR conceptual

[Rucap09]

Confused about two statements in BR Gen Chem and wondering if anyone can sort them out.

In the opening passage for the Phases and Phase Changes chapter, it is stated that "Gases have the most kinetic energy of the three common phases, and it exists in the translational, vibrational, and rotational forms".

Yet in a passage on heat capacity for phase changes, the following is stated: "The heat capacity of the liquid is the greatest of the three phases. This is not unusual, given that liquids can absorb intermolecular vibration energy as well as translational kinetic energy. Solids can only vibrate, and gases can only move translationally."

If gases have the largest composite kinetic energy due to having three types of motion, how is that reconciled with the claim that they only move translationally? Shouldn't they be able to absorb energy as an increase in both their vibrational and rotational motions in addition to translational?

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[DrknoSDN]

and gases can only move translationally.

Because it's in a passage and not the actual text it's using practical information. The vibration and rotation are insignificant to the total energy.

gases have the largest composite kinetic energy due to having three types of motion

It's not due to having 3 types of motion, it's just a fact that they have the most energy and also as a separate fact have 3 types of motion.

 

[Rucap09]

If vibrational and rotational energy are insignificant to the total energy in comparison to translational energy, why in liquids would the contribution of energy absorbed that causes you to move along the spectrum of low-to-high vib/rot energy cause liquids to have the highest heat capacity?

Are you saying that for liquids, vibrational and rotational energy make up a larger contribution of total KE and thus act as a larger "sink" for energy to be placed into, whereas for gases the majority of energy is placed into translational energy and there is less allowance for storing energy as vibrational and rotational energy?

it's just a fact that [gases] have the most energy and also as a separate fact have 3 types of motion

Solids can only vibrate, and gases can only move translationally

Do you have a source for this? These are pretty contradictory statements. I would also assume that gases have vibrational and rotational energy, but I'm not seeing anything about the differential contribution in these two phases anywhere.

 

[DrknoSDN]

http://www.clickandlearn.org/gr9_sci/particle_theory.htm
"Particles of solids possess only vibrational energy."... "Particles of gases have rotational, translational and vibrational energy."

Sorry for slow response. I believe that you won't find much information on the contribution from vibrational and rotational energy about gases because it's not a significant part of the total energy. Gas molecules are so spread out that they don't interact the same way solids and liquids do. There is rotation (in non monatomic gases), and vibration in some gases like H2O, but it's not as significant as the translational portion.

I looked around for some very reputable sources (universities) saying a gas has more energy than a liquid or solid but if you do a basic google search "gas has more energy than liquid" you will get tons of sites explaining why it's true.
Google Search Results

[Edit May 30]
Found this: http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/inteng.html