I am under the water pls help me

Astudent reacts 13 moles of iron with 21 moles of oxygen according to the following equation:

Which of the following describes a compound? (hint: carbon and oxygen bo a. a piece of pure carbon, containing only carbon atoms b. oxygen gas surrounding a solid piece of carbon c. a substance made of two oxygen atoms for each carbon atom carbon and oxygen atoms mixed without being bonded together

What is the energy in joules of a mole of photons associated with visible light of wavelength 486 nm?