1.why leaf is boiled in methylated sprit 2.why potassium hydroxide is used in mohl's half leaf experiment answer say

Question 1: why leaf is boiled in methylated sprit

A leaf is boiled in methylated spirit (ethanol) to remove chlorophyll. This is done because chlorophyll is green and would mask the color change when testing for starch with iodine solution, making it difficult to observe the results clearly.

---

Question 2: why potassium hydroxide is used in mohl's half leaf experiment

Potassium hydroxide ($\ce{KOH}$) is used in Mohl's half-leaf experiment to absorb carbon dioxide ($\ce{CO2}$) from the air within the flask. This creates a $\ce{CO2}$-free environment for the part of the leaf inside the flask, demonstrating that carbon dioxide is essential for photosynthesis.