Why do molecules vibrate under higher temperatures?

[LogicalAcid]

This question has been bugging me for a while, I thought that it was due to the atoms electrons moving faster, making the atom basically also move around more.

 

[brewAP2010]

Molecules are always moving and when you heat them up they move faster causing vibration.

 

[mrspeedybob]

Atomic / molecular kinetic energy is heat by definition so it's kind of meaningless to ask why atoms / molecules move more when hot.

 

[sophiecentaur]

Is this a question about the difference between translational kinetic energy and vibrational KE?

 

[tatiana]

Molecules tebd to move faster unter higher temeratures because space expands and teher is more room for them to flow, when it gets colder and temperatures drop, the molecules move slower and bcome more copact. Just think about yourself, its easier to move around and do things when your warm, but when your colder, you huddle and try not to move

 

[sophiecentaur]

You are confusing the order of things here. As the energy in the system increases the vibrations and linear movements increase in amplitude. This increases the pressure on the walls / outside of the 'object' ( or gas) and, if the applied pressure is not maintained, the object will expand until there is, again, a balance.
The temperature is, by definition, the average kinetic energy of the particles.