In the reaction `Li_3^6 + (?) to He_2^4 + H_1^3`. The missing particle is:

Options

A. Electron
B. Neutron
C. Proton
D. Deuteron

Answer

To solve the problem of identifying the missing particle in the nuclear reaction \( Li_3^6 + (?) \rightarrow He_2^4 + H_1^3 \), we will follow these steps:

### Step 1: Identify the Components of the Reaction
We have:
- Reactants: \( Li_3^6 \) (Lithium-6) and an unknown particle (let's call it \( X \)).
- Products: \( He_2^4 \) (Helium-4) and \( H_1^3 \) (Tritium).

### Step 2: Write Down the Conservation Laws
In nuclear reactions, both atomic mass and atomic number must be conserved. This means:
1. The total atomic mass on the reactant side must equal the total atomic mass on the product side.
2. The total atomic number on the reactant side must equal the total atomic number on the product side.

### Step 3: Calculate Total Atomic Mass
- Atomic mass of \( Li_3^6 \) = 6
- Atomic mass of \( He_2^4 \) = 4
- Atomic mass of \( H_1^3 \) = 3

Setting up the equation for atomic mass:
\[ 6 + A = 4 + 3 \]
Where \( A \) is the atomic mass of the unknown particle \( X \).

Calculating:
\[ 6 + A = 7 \implies A = 7 - 6 = 1 \]

### Step 4: Calculate Total Atomic Number
- Atomic number of \( Li_3^6 \) = 3
- Atomic number of \( He_2^4 \) = 2
- Atomic number of \( H_1^3 \) = 1

Setting up the equation for atomic number:
\[ 3 + Z = 2 + 1 \]
Where \( Z \) is the atomic number of the unknown particle \( X \).

Calculating:
\[ 3 + Z = 3 \implies Z = 3 - 3 = 0 \]

### Step 5: Identify the Missing Particle
Now we have determined that the unknown particle \( X \) has:
- Atomic mass \( A = 1 \)
- Atomic number \( Z = 0 \)

The only particle that fits this description is a neutron, which has an atomic mass of 1 and an atomic number of 0.

### Conclusion
The missing particle in the reaction \( Li_3^6 + (?) \rightarrow He_2^4 + H_1^3 \) is a **neutron**.

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