what is the composition of atmosphere
The atmosphere looks like a blanket of gas when you look at it from space or the ground. When scientists started to examine the atmosphere, they noticed that there were different parts and different layers. There are layers of different molecules, temperatures, and pressures. Overall, the atmosphere is made up of a few main molecules. The air above you is made of 78% nitrogen (N2), 21% oxygen (O2), 0.9% argon (Ar) and 0.04% carbon dioxide (CO2). That's it. The rest of it is made of things called trace elements.