Question

Boojho wanted to test the presence of starch in leaves. He performed the following steps.

1. He took a leaf and boiled it in water.
2. He placed the leaf in a petri dish and poured some iodine over it.

He did not get the expected result. Which step did he miss? Explain.

Answer 1

After boiling the leaf in water, it has to be boiled in alcohol so that chlorophyll is removed and the green colour of the leaf comes out. Boojho did not boil the leaf in spirit (alcohol) to remove the chlorophyll and therefore, he did not get the expected result (i.e. change in colour of the leaf).