How does the earth’s early atmosphere composition differ from today’s composition?

Hint: The earth was formed from a hot mixture of gases and solids and had no atmosphere, gases poured out of volcanoes made the atmosphere. With the evolution of living organisms, the composition of today’s composition changed.

Complete answer: Around 4.6 billion years ago, the earth was formed from a hot mixture of gases and solids. The earth had no atmosphere. The surface of the earth was molten. When the temperature of the earth decreased and as it cooled, an atmosphere formed majorly from gases poured out from the volcanoes.
Then the atmosphere included sulfide, methane, hydrogen, carbon dioxide. The carbon dioxide was ten to 200 times as compared to today's atmosphere. The surface of the earth cooled and solidified enough for water to collect it, after about half a billion years ago.
As we compare the composition of the atmosphere has changed. Earlier the atmosphere was hazy, the mixture was unfamiliar but the skies are blue now. With the development of the atmosphere, life began and evolved. With the evolution of living organisms, the change of atmosphere took place.
Around 350 million years ago, oxygen made up twenty percent of the atmosphere, and in the next fifty million years, the level of oxygen rose to more than thirty-five percent. As of now, twenty-one percent of the atmosphere consists of oxygen.

Note: The blanket of gases that surround the earth is known as the atmosphere. The atmosphere has five different layers. The layers of the atmosphere are the troposphere, stratosphere, mesosphere, thermosphere, and exosphere.