# Why does stretching of rubber decrease entropy?

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## Why does stretching of rubber decrease entropy?

As the rubber band is being stretched Ω decreases as a function of length and therefore the entropy decreases as a function of length.

## Does stretching of rubber increase entropy?

When stretched the polymer strands should be more aligned and straighten out along the direction of the stretching. When you relax it the strands go in all directions, or become more disordered. For this change the entropy increases, which means the heat is positive.

What happens when you stretch the rubber bands Why is this so?

When you stretch a rubber band, you are aligning the polymers and eliminating all the chaotic tangles. In effect, you are lowering the entropy of the molecules, but the universe prefers to move towards entropy. Order requires energy and effort, while entropy is the natural direction of matter.

Why rubber band is stretched how it is connected to the elastic rebound theory?

This is what happens in a rubber band. As you stretch a rubber band, the material stores elastic energy, and its desire to snap back is the stored elastic energy. Once there is a lot of elastic energy stored, you can let it go.

### What is entropy for stretching of rubber?

Entropy increases in stretching the rubber band because when we stretch rubber band, the band should be more aligned and straighten out along the direction of the stretching. So when we relax it the band go in all directions. So become more distorted.

### Why the stretching of a rubber band is reversible change?

When we strech a rubber with force of our hands, it undergoes a change and its length increases. But, on releasing the force, rubber comes back to it’s original length. So the streching of rubber is a reversible change.

How does elastic rebound cause earthquakes?

The rock becomes distorted, or bent, but holds its position until the earthquake occurs, and the rock snaps back into an unstrained position, releasing energy that produces seismic waves.

Is stretching a rubber band reversible?

The stretching and relaxing of a rubber band is an example of a reversible process.

#### What change happened in the rubber band?

When stretched, it changes its shape and when the applied force is removed, it regains its original shape. That is why a rubber band changes its shape even though it is a solid. Also, if excessive force is applied then the rubber band would break.

#### Why does stretching a rubber band increase entropy?

Heating the rubber band contracts it. Therefore, according to LeChatelier’s principle, stretching the rubber band MUST increase it temperature, because by getting hotter it tends to contract, resisting the stress of stretching. Slow stretching and relaxing of a rubber band has no effect on entropy of band as neither heat is generated nor supplied.

What happens during the stretching of a rubber?

Just rapid stretching to a point and holding it raises the entropy initially as the molecules are excited and after the molecules of rubber band settle in their new positions, entropy drops to initial. The entropy of the universe, though, increases.

Why is the internal energy of rubber increasing?

So you are doing positive work on the rubber, and it is doing negative work on you (its surroundings). So, from the first law of thermodynamics, if the process is adiabatic, the internal energy of the rubber is increasing. The internal energy of rubber is known from observations to be nearly a function only of temperature.

## What happens when you change the length of a rubber band?

Any change in the length of the band will result in an increase or decrease in the balance reading. Attach one end of a cut rubber band to a clamp that is attached to a ring stand. Attach a weight to the other end of the band. Use a ruler or other measurement scale next to the weight to observe any change in length.