The diagram given below represents an experiment to prove the importance of a factor in photosynthesis. Answer the questions that follow: The diagram given below represents an experiment to prove the importance of a factor in photosynthesis. Answer the questions that follow:
What is the purpose of keeping KOH in the flask?
Topic: Purpose of KOH
Answer
Potassium hydroxide is a strong alkali that ABSORBS ALL THE CARBON DIOXIDE from the air inside the flask, so that the enclosed leaf is deprived of it.
State WHAT it does (absorbs carbon dioxide) and WHY (so the leaf is deprived of it). An answer saying only "to absorb gases" is too vague.
WHY AN ALKALI: carbon dioxide is ACIDIC, and alkalis absorb acidic gases. That is also why SODIUM HYDROXIDE can be used instead — any strong alkali serves.
This makes the experiment a fair test: the leaf in the flask differs from the one outside in exactly one respect.