What is the charge of oxygen in Na2O?

-2

Explanation:

- Look up oxidation rules. Most always, oxygen is a -2.

- If you want more info, Na would be +1 because 1 + 1 = 2, which balances out the -2 on Oxygen.

- Hope this helps! If you need more help or a further explanation please let me know.

answer : a model is often used to explain and make things easier to understand when any scientific topic needs to be demonstrated and explained.

as in this case where a scientist wants to use a model to present the results of his detailed scientific investigation. he should do it as it will him to make the audience understand the concept in a much better way. also, it can be changed according to new scientific understandings.