Which of the following compounds is the most reduced?

ethene

carbon dioxide

propanone

ethane

The correct answer is ethane.

Explanation:

Most reduced species is defined as the species which contains the maximum number of hydrogen atoms and cannot be further reduced.

Oxidized species are the species which can be further reduced.

From the given options:

1.) Ethene: This specie has 4 hydrogen atoms and can be further reduced into ethane using where, nickel acts as a catalyst.

2.) Carbon dioxide: This specie does not contain hydrogen at all. Hence, it is not a reduced specie.

3.) Propanone: This specie contains 6 hydrogen atom and can be further reduced into propanol using .

4.) Ethane: This specie contains 6 hydrogen atoms and cannot be further reduced.

From above information, the most reduced specie is ethane.