For the iodine test, How does boiling alcohol speed up the diffusion of chlorophyll out of the cells? Why does the leaf become crisp and breaks easily after it has been dehydrated by alcohol? For the detection of oxygen produced from photosynthesis, Why does sodium hydrogencarbonate solution decompose in water? How does the stoppers allow CO2 outside the funnel diffuse to the aquatic plant? (I really dont get it) For the investigation of the need for CO2 in photosynthesis, How does potassium hydroxide absorb CO2?