An element A has atomic mass 27 and atomic number 13. Its ion is represented by `A^(x +)`. The value of x is

Explanation

To solve the problem, we need to determine the value of \( x \) in the ion representation \( A^{(x +)} \) for the element A, which has an atomic mass of 27 and an atomic number of 13.

### Step-by-Step Solution:

1. **Identify the Element**:
- The atomic number of the element A is 13. This means it has 13 protons in its nucleus.

2. **Determine the Electronic Configuration**:
- The electronic configuration of an element is determined by distributing its electrons in various shells.
- For atomic number 13, the distribution of electrons is as follows:
- K shell: 2 electrons
- L shell: 8 electrons
- M shell: 3 electrons
- Therefore, the electronic configuration of element A is \( 2, 8, 3 \).

3. **Identify Valence Electrons**:
- The valence shell for element A is the M shell, which contains 3 electrons. Thus, A has 3 valence electrons.

4. **Determine Ion Formation**:
- Since element A has 3 valence electrons, it can achieve a stable electronic configuration (octet) by losing these 3 electrons.
- When it loses 3 electrons, it becomes a cation (positively charged ion).

5. **Determine the Charge of the Ion**:
- The loss of 3 electrons results in a charge of \( +3 \) on the ion.
- Therefore, the ion can be represented as \( A^{(3+)} \).

6. **Conclusion**:
- The value of \( x \) in \( A^{(x +)} \) is 3.

### Final Answer:
The value of \( x \) is 3.

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