Question

What causes acid rain?

Answer 1

smoke given out by factories and vehicles rise up in the air and gets accumulated in the clouds.
when rain falls to the earth the acids present in clouds also comes down with rain.
the main causes of acid rains are:
smoke from factories and industries
smoke from vehicles

Answer 2

acid rain is cause due to the excess of sulphur and nitric oxide in air. when we burn any fuel it releases the sulphur or nitric oxide when it goes upward it get mixed with the water vapours and comes down in form of rain
main reasons for causing acid rain is pollution from the vehicles or factories