Nuclear Reactions Diagram with Isotope Names and Reaction Types

Let’s solve this step by step.

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Top Diagram (Reaction 1):

We see two small nuclei combining to form a larger one, plus energy. That’s fusion.

Each starting nucleus has:
- 1 proton (p)
- 1 neutron (n)

So mass number = protons + neutrons = 1 + 1 = 2

Element with 1 proton is Hydrogen (H) → so each is H-2

They combine to make a nucleus with:
- 2 protons
- 2 neutrons → mass = 4

Element with 2 protons is Helium (He) → so product is He-4

So the reaction is:
H-2 + H-2 → He-4 + energy

That matches option b in question 1.

Also, for the isotope names in the top diagram:

- Left two circles: both are H-2
- Right circle: He-4
- Reaction type: Fusion

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Bottom Diagram (Reaction 2):

A neutron hits a big nucleus (92p, 143n → total mass = 92+143=235). So that’s U-235.

It splits into:
- One piece: 56p, 85n → mass = 56+85=141 → element with 56 protons is Barium (Ba) → Ba-141
- Other piece: 36p, 56n → mass = 36+56=92 → element with 36 protons is Krypton (Kr) → Kr-92
- Plus 3 neutrons and energy

This is fission.

So the full reaction is:
1 neutron + U-235 → Ba-141 + Kr-92 + 3 neutrons + energy

That matches option a in question 2.

Isotope names in bottom diagram:

- Big nucleus before split: U-235
- Top fragment: Ba-141
- Bottom fragment: Kr-92
- Reaction type: Fission

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Now fill in all blanks from the diagram:

Top Reaction:

1. Reaction Type → Fusion
4. Isotope Name (left first) → H-2
4. Isotope Name (left second) → H-2
4. Isotope Name (right) → He-4

Bottom Reaction:

1. Reaction Type → Fission
2. Isotope Name (big nucleus) → U-235
2. Isotope Name (top fragment) → Ba-141
2. Isotope Name (bottom fragment) → Kr-92

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Multiple Choice:

1. Correct equation for top diagram → b. H-2 + H-2 → He-4

2. Correct equation for bottom diagram → a. 1 neutron + U-235 → Ba-141 + Kr-92 + 3 neutrons + energy

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Final Answer:

Top Diagram Blanks:
- Reaction Type: Fusion
- Left isotopes: H-2, H-2
- Right isotope: He-4

Bottom Diagram Blanks:
- Reaction Type: Fission
- Big nucleus: U-235
- Fragments: Ba-141, Kr-92

Multiple Choice:
1. b
2. a