Fill in the blank in the given nuclear reaction :
_______ `+""_(13)^(27)Al to""_(12)^(25)Mg+""_(2)^(4)He`

Explanation

To solve the nuclear reaction and fill in the blank, we will use the law of conservation of mass and charge. The equation given is:

\[ \_\_\_\_ + \, _{13}^{27}Al \rightarrow _{12}^{25}Mg + \, _{2}^{4}He \]

### Step-by-step Solution:

1. **Identify the Known Values**:
- We have Aluminum (Al) with atomic number 13 and mass number 27: \(_{13}^{27}Al\).
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