Final answer:
The final oxidation number of carbon in the chemical reaction 6CO2 + 6H2O -> C6H12O6 + 6O2 is -1 for each carbon atom in the glucose molecule (C6H12O6).
Step-by-step explanation:
The student asked about the final oxidation number of carbon in the photosynthesis reaction 6CO2 + 6H2O -> C6H12O6 + 6O2. The carbon in glucose (C6H12O6) has an oxidation number of -1 when we assign oxidation numbers based on common rules: oxygen is usually -2 and hydrogen is +1. However, to find the average oxidation state of the carbon atoms in glucose, we look at the overall oxidation state for all carbons in the molecule. As a molecule of glucose is neutral, the sum of oxidation numbers for C, H, and O must equal zero. With H being +1 each and there being 12 H atoms, this contributes +12. For O being -2 each and there being 6 O atoms, this contributes -12. Therefore, the 6 carbons must collectively have an oxidation state that balances this out to equal 0, so they are -1 each. Thus, when we average it out for each carbon atom in glucose (C6H12O6), it will end up being -1.