CBSE Class 8 Answered

Benefits of lightning: 

1. Lightning strikes dissolve unusable nitrogen in water and form a natural fertilizer which is absorbed by the roots of plants. Thus, lightning helps for nitrogen fixation.

2. Lightning also produces important gas called ozone which protects our planet from the harmful UV rays. 

3. Nitrogen is important for other living beings also. The nitrogen existing in nature is just inhaled and exhaled by us without being used by our body. Proteins in our body are made of nitrogen. But the nitrogen existing in nature has 3 electron bonds which need to be broken. The breaking of these bonds requires high energy. Lightning provides this energy and when it strikes through the atmosphere the nitrogen bonds breaks and get mixed with oxygen and hydrogen forming nitrates. Without nitrogen the existence of life on the earth is impossible. Hence, lightening plays an important role in the origin and evolution of life on earth.