Final answer:
Methane (CH4) is the molecule in the most reduced state of carbon listed, as it has the maximum number of hydrogen atoms and no carbon-oxygen bonds.
Step-by-step explanation:
The question is which of the following molecules is in the most reduced state of carbon: a) Methanol, b) Methane, c) Carbon dioxide, d) Formaldehyde. Methane (CH4) represents the completely reduced form of an organic molecule containing one carbon atom because it has the maximum number of hydrogen atoms bonded to carbon, and no carbon-oxygen bonds.
As we sequentially replace each carbon-hydrogen bond with a carbon-oxygen bond, the molecule becomes oxidized to form methanol (CH3OH), then formaldehyde (CH2O), and finally carbon dioxide (CO2), which is the most oxidized form of carbon in the given examples. Thus, methane is in the most reduced state as compared to methanol, formaldehyde, and carbon dioxide.