In the following reaction, x is
`xNa+O_(2)to`

Explanation

To solve the problem, we need to determine the value of x in the reaction involving sodium (Na) and oxygen (O₂) that forms sodium oxide (Na₂O). Here’s a step-by-step breakdown of the solution:

### Step 1: Write the unbalanced chemical equation
The reaction between sodium and oxygen can be represented as:
\[ x \, \text{Na} + \text{O}_2 \rightarrow \text{Na}_2\text{O} \]

### Step 2: Identify the products
When sodium reacts with oxygen, it forms sodium oxide (Na₂O).

### Step 3: Balance the chemical equation
To balance the equation, we need to ensure that the number of sodium (Na) and oxygen (O) atoms on the reactant side equals the number on the product side.

1. In Na₂O, there are 2 sodium atoms and 1 oxygen atom.
2. On the reactant side, we have x sodium atoms and 2 oxygen atoms from O₂.

### Step 4: Set up the balancing
To balance the equation:
- Since there are 2 sodium atoms in Na₂O, we need 2 sodium atoms on the reactant side. Therefore, we set x = 4 because we need 4 sodium atoms to provide 2 Na₂O molecules when balanced with oxygen.

### Step 5: Write the balanced equation
The balanced equation will then be:
\[ 4 \, \text{Na} + \text{O}_2 \rightarrow 2 \, \text{Na}_2\text{O} \]

### Conclusion
Thus, the value of x is 4.

### Final Answer
x = 4

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