Question

A. What do you observe when carbon dioxide gas is passed through lime water?
B. Explain nitrogen fixation process.

Answer 1

A. When carbon dioxide gas is passed through lime water, it forms calcium carbonate which is white precipitate. This gives the milky white appearance to the solution.

B. Plants cannot take nitrogen directly from the air. The nitrogen is converted into a usable form such as nitrates and nitrites for plants. These nitrites and nitrates are added to the plants as fertilizers and plants absorb the nitrogen in the form of nitrites and nitrates from soil. This process is called nitrogen fixation.