An ion `X^(2-)` contains 10 electrons and 8 neutrons. What are the atomic number and mass number of the element X? Name the element.

Explanation

To solve the question, we need to determine the atomic number and mass number of the ion \(X^{2-}\) which contains 10 electrons and 8 neutrons. We will also identify the element represented by \(X\).

### Step 1: Determine the number of protons
The ion \(X^{2-}\) has a charge of -2, which means it has gained 2 extra electrons compared to its neutral form. Since it has 10 electrons in the anionic form, we can find the number of electrons in the neutral atom \(X\):

\[ \text{Number of electrons in neutral atom} = \text{Electrons in ion} - \text{Charge} = 10 - 2 = 8 \]
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