Question

which statements correctly describe what happens to the atoms in co₂ molecules during photosynthesis? select all that apply. the carbon atoms will lose electrons and be oxidized. the carbon atoms will gain electrons and be reduced. the carbon atoms will end up in the carbohydrate product. the oxygen atoms will end up in the molecular oxygen product. incorrect molecular oxygen is a product of photosynthesis, but its origin is not the oxygen atoms in co₂.

Explanation:

• In photosynthesis, carbon in \(CO_2\) (oxidation state \(+4\)) is reduced (gains electrons) to form carbohydrates (where carbon has a lower oxidation state). So, the statement "The carbon atoms will gain electrons and be reduced" is correct.
• The overall equation of photosynthesis is \(6CO_2 + 6H_2O

ightarrow C_6H_{12}O_6+6O_2\). Carbon from \(CO_2\) is incorporated into the carbohydrate (\(C_6H_{12}O_6\)), so "The carbon atoms will end up in the carbohydrate product" is correct.

• The oxygen in \(O_2\) (product of photosynthesis) comes from \(H_2O\) (not from \(CO_2\)). The reaction for the splitting of water is \(2H_2O

ightarrow O_2 + 4H^{+}+4e^{-}\). So, the statement "The oxygen atoms will end up in the molecular oxygen product" is incorrect.

Answer:

• The carbon atoms will gain electrons and be reduced.
• The carbon atoms will end up in the carbohydrate product.