What would happen if an objects molecules stopped moving completely? What would happen if an objects molecules

Question

started to move faster than average or slower than average? Why do molecules have a tendancy to move and why cant they stop? Would life sese to exist if molecules reached absolute zero motion?

Answer 1

According to the uncertainty principle, you can't reach absolute zero.

Answer 2

"Temperature" is defined as the amount of movement among the components of something (like the molecules in air, in a liquid or in a solid object). The hotter things are, the more the molecules are jostled around.

In a solid, the molecules are held in place relative to other molecules by a bond. They will move around their average position but not very much. As the temperature climbs, they will move too much and break the bond (the solid melts).
In the liquid, the molecules are still rubbing against each other (if you can call that rubbing), but they are moving around compared to their neighbors. There is still some tension keeping the liquid together. As the temperature climbs even more, the individual movements become too much for the tension: the molecules are no longer "in contact" and you have a gas.

As the temperature climbs even more, the molecules are moving about very violently, hitting each other. The pressure climbs (or the volume expands). As the temperature climbs even more, the collisions may be violent enough to knock electrons out of their orbits (the atoms or molecules are ionized). Get enough ionization and the gas starts to behave very differently: you have a plasma.

get enough free electrons and the plasma gets opaque (maybe not to all frequencies). Free electrons interact very readily with photons. They get in each other's way.

Keep going and you could eventually knock away all electrons and even cause such violent collisions that the atoms will combine (fusion) and liberate even more energy; this new energy will increase the temperature... and so on.

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Run the film backwards for the cooling sequence.

At absolute 0, there is still some residual movement (called zero-point energy). There is a link with Heisenberg's principle of uncertainty. If movement stopped completely, you would know BOTH the position and speed (0) of the atom very precisely, and that is not allowed.

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Chemical reaction rates increase with increasing temperature. The rate drops with dropping temperatures. Chemical reactions are pretty well impossible at absolute zero, so we can suppose that life can't exist (life requires constant chemical reactions).

In our case (and for living things on this planet), all our cells contain large quantities of water (relatively speaking). When frozen, water crystalises and expands, separating the components -- enzymes, amino acids, etc -- and keeping them from moving about. Thus, well before reaching absolute zero, our lives are done.

In addition, at the molecular level, ice crystals are sharp and will cut through the complex biological molecules. So even if you were to thaw the cells, you only get a mushy mix instead of a collection of enzymes, amino acids, etc. that should be happy to start interacting again.

Answer 3

If the molecules in an object stop moving completely, the object would be at a temperature of absolute zero.

Answer 4

sese ? try cease

make them cold ...and they'll stop