7. What are the different stages of development of atmosphere? – Exp

1.	7. What are the different stages of development of atmosphere? – Explain.
Answer» When\xa0Earth formed\xa04.6 billion years ago from a hot mix of gases and solids, it had almost no\xa0atmosphere. The surface was molten. As\xa0Earth\xa0cooled, an\xa0atmosphere formed\xa0mainly from gases spewed from volcanoes. It included hydrogen sulfide, methane, and ten to 200 times as much carbon dioxide as today\'s\xa0atmosphere. The\xa0atmosphere\xa0can be divided into layers based on its temperature.\xa0These layers are the troposphere, the stratosphere, the mesosphere and the thermosphere. A further region, beginning about 500 km above the Earth\'s surface, is called the exosphere.\xa0Water vapor, carbon dioxide, methane, ammonia, and other gases similar to the ones produced by volcanoes today\xa0were\xa0expelled.\xa0Over\xa0a vast amount of\xa0time, millions of years, the\xa0earth\xa0gradually cooled. ... From these clouds, the oceans formed and the oceans absorbed a lot\xa0of the\xa0carbon dioxide\xa0in the atmosphere.

7. What are the different stages of development of atmosphere? – Explain.