oxygen
Gas was lacking from Earth's early atmosphere in the early Precambrian era because the primitive atmosphere was composed mainly of hydrogen and helium, which were lost over time. The formation of the Earth's magnetic field and the development of the ozone layer prevented the atmosphere from being stripped away by solar winds, leading to the accumulation of gases like carbon dioxide and water vapor over billions of years.
During the Precambrian time, the Earth's atmosphere lacked free oxygen, and the early atmosphere was likely composed of gases such as methane, ammonia, and carbon dioxide. Throughout the Precambrian, there were significant changes in atmospheric composition due to volcanic activity and the evolution of photosynthetic organisms that contributed oxygen to the atmosphere.
The Earth's Precambrian atmosphere was primarily composed of carbon dioxide, methane, ammonia, and water vapor. It lacked oxygen and had higher levels of greenhouse gases compared to the present atmosphere. This environment supported the evolution of early life forms such as bacteria and algae.
nitrogen
oxygen
no
photosynthsis
Hydrogen and helium
energy from the sun,lightening,earths heat triggered chemical reaction for the early gases of the earth combined
Carbon dioxide
oxygen
Methane gas