To prove that a certain fruit (in this case, an orange) indeed contains a certain compound (in this case, vitamin C); then the vitamin C should be extracted and isolated from the orange and must be confirmed by molecular analysis. The extraction process involves using chemicals (i.e. 6% MPA), and procedures such as centrifugation and filtration. Then the extract is stored and subjected to high-performance liquid analysis (HPLC) to measure the vitamin C content.
Maybe not because after light increases stomas will decrease and after that plant leaf will take less co2 and less co2 mean less synthesis in the plant.
