In the product

The mass of carbon element is 44× 12/44 = 12g.

The mass of hydrogen is 36× 2/ 18 = 4g.

The mass of oxygen is 44× 32/44+36×16/18 = 64g.

The total mass of the product is 80g, so the mass of oxygen element obtained from air is 80-32 = 48g, and the mass of oxygen element in methanol is 32- 12-4 = 16g.

Methanol is composed of carbon, hydrogen and oxygen, and their mass is 12g, 4g and 16g respectively.

I hope it will be helpful to your study.

Please use O(∩_∩)O if you are satisfied. Thank you.

Welcome to ask O(∩_∩)O Thank you.

I wish you progress in your study ~