Question

mention the use of alcohol and KoH in the experiment of photosynthesis

Answer 1

by boiling the leaf in alcohol the leaf will loose all its pigments and KOH is used to prove CO2 is use ful in photosynthesis.it is used to observe the Co2 in the beaker were half of the leaf is placed. hope this helps u my frnd.

Answer 2

In the experiment of photosynthesis we basically need to show that leaves make starch in presence of sunlight.
In this experiment alcohol is used to boil the leaves so that the can become soft and decolourise , i.e chlorophyll can be removed. 

always remember koh is used to absorb CO2 so in this experiment also KOH is used to do so