Which of the following is a fusion reaction?
a.) uranium-235 absorbing a neutron and splitting into xenon-140, strontium-94, and two neutrons
b.) hydrochloric acid combining with sodium hydroxide to form nacl and water
c.) carbon-14 decaying into nitrogen-14 and a beta particle
d.) curium-246 combining with carbon-12 to form nobelium-254 and four neutrons

We want to see what happens to the particle's speed in a given material as the temperature changes (increases in this case) and it faces a change of phase.

We will see that the particles in the gas (vapor of water) have a larger speed than the ones in the liquid water.

To see this, first, we need to understand how the temperature manifests in a given material.

As we increase the temperature of the material, the kinetic energy of the particles that make the material increase (thus the speed increases). This causes the particles to move more, and this is why as we increase the temperature, is likely to see an increase in the volume.

This is the reason of why we usually see that a solid has less volume than a liquid, and a liquid has less volume than a gas (for the same mass of the same material).

Then as we increase the temperature of liquid water and that water starts to change of phase (by boiling) the kinetic energy of the particles increase, and thus, the speed increases.

Then the particles will be moving faster than the particles of the water in the pan.

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