Answer:
- Third choice: Model 1 shows reactions in the sun and Model 2 shows reactions in the nuclear power plants.
Step-by-step explanation:
There are two kind of nuclear ractions: fusion and fission reactions.
Both release a huge amount of energy in different ways.
Fusion reactions are nuclear reations in which two smaller (lighter) atoms combine into a larger (heavier) atom, with the respective release of energy.
That is what model 1 shows:
- Model 1: Atom 1 + Atom 2 = Atom 3 + energy
That is the process that happens and is responsible for the huge amount of heat produced in and released by the Sun.
In the Sun two atoms of hydrogen fuse into a larger atom of helium.
That is represented by the nuclear reaction:
→
+ some other particles
Since fusion reactions need extremely high temperatures and pressure to start and keep going, the technology to use them economically is still in development.
Fission reactions involve the split of the atom into smaller (lighter) atoms, releasing a huge amount of energy.
That is depicted by the model 2:
- Model 2: Atom 4 = Atom 5 + Atom 6 + energy
As you see one atom is being splited in two atoms with release of energy.
And indeed, that is the technology used by the nuclear power plants.
An example is the fission of uranium-235
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