You're asking about the reaction of sodium (Na) with oxygen (O₂), which produces sodium oxide (Na₂O). Here's how to solve this problem:

1. Balanced Chemical Equation:

First, we need a balanced chemical equation:

4 Na + O₂ → 2 Na₂O

This equation tells us that 4 moles of sodium react with 1 mole of oxygen to produce 2 moles of sodium oxide.

2. Mole Ratio:

The mole ratio between sodium and sodium oxide is 4:2, which simplifies to 2:1. This means that for every 2 moles of sodium that react, you'll get 1 mole of sodium oxide.

3. Calculate Moles of Sodium Oxide:

Since you're starting with 10 moles of sodium, we can use the mole ratio to find the moles of sodium oxide:

(10 moles Na) * (1 mole Na₂O / 2 moles Na) = 5 moles Na₂O

Therefore, 5 moles of sodium oxide will be produced when 10 moles of sodium react with oxygen.