The gas that surrounds the Earth is called air, which is a mixture of different gases. The most abundant gas in the air is nitrogen (N2), followed by oxygen (O2). Here's a breakdown of the main gases and their percentages:

* Nitrogen (N2): 78%

* Oxygen (O2): 21%

* Argon (Ar): 0.93%

* Carbon dioxide (CO2): 0.04%

* Other gases: Less than 1% (including neon, helium, methane, krypton, hydrogen, and xenon)

This mixture of gases is what makes up the Earth's atmosphere.