mass vs heat storage ability

[Erich]

As temp goes up the atoms vibrate more vigorously in the crystal lattice

Absolute zero temp is the temperature where all atomic vibration stops.

[J Tiers]

Water has a high heat capacity in part because the molecules have so many vibrational modes.

Other materials may be limited due to crystal lattice structure, etc.

[ed_h]

While the "planetary model" of the atom with its electrons in orbits around the nucleus may still be a useful picture for some things, it's pretty outdated and electrons don't really do that.

Ed

[rohart]

Electrons are bound to atomic nuclei with forces that are massively greater than the forces that hold atoms in position in solid structures. Electrons couldn't care less if a substance gets hotter. Having said that, a photon will be absorbed by an electron and shift it up an energy level, which will add a small amount of momentum to the atom, and cause it to vibrate in position a little more.

It's the amplitude of the vibration of atoms about their equilibrium positions that we measure as temperature.

Brownian motion is the motion of minute visible particles - like particles of smoke or liquid borne dust or large bacteria - as they are buffetted around by collisions with atoms or molecules of the medium in which they are suspended. Large particles would be buffetted so often it would even out and you'd see nothing. Small particles may get hit just that bit more on one side than the other for us to see a little movement, jiggling about. This is Brownian motion. It's not the bulk gas or liquid we're seeing - it's the jiggling about of the larger particles. In a gas, the atoms or molecules are slamming into each other and bouncing off all the time at high speed, and far too fast to see. We see the effect of a larger particle being hit unevenly and jiggling about.

Now having drooled all that out, I'll qualify it all by saying it's old science from the 60's and 70's, but I believe I can get away with it as I haven't had to refer to anything of quantum size. Everything I've mentioned is pretty basic large scale stuff.