The pie chart below shows the major components of the Earth's atmosphere.
Components of the Atmosphere
Nitrogen (78%)
Oxygen (21%)
Other Gases (1%)
(including water vapor, argon,
carbon dioxide, neon, helium,
hydrogen, methane, ozone)
Based on this chart, the Earth's atmosphere can best be described as
A.
a pure substance.
B. a mixture of gases.
C.
a mixture of liquids.
D.
a compound of solids.