Answer:
- From octane: 
- From ethanol: 
Explanation:
Hello,
At first, for the combustion of octane, the following chemical reaction is carried out:

Thus, the produced mass of carbon dioxide is:

Now, for ethanol:


Best regards.
Answer:
Ocean, lakes and rivers. Are all liquids.
Explanation:
Ocean, lakes and rivers. Are all liquids. Snow starts off as a liquid, evaporates into a gas and camoes back as snow.
Physical change .. you cannot undo chemical ... physical is like bending , shattering a mirror , denting something ..
chemical would be rust or something .