Answer:
You may be referring to the gas that makes up 21% of the earth's atmosphere, which is oxygen.
Explanation:
According to NASA, the gases in Earth's atmosphere include:
Nitrogen — 78 percent
Oxygen — 21 percent
Argon — 0.93 percent
Carbon dioxide — 0.04 percent
(Trace amounts of neon, helium, methane, krypton and hydrogen, as well as water vapor)
1. Physical matter
2. Chemical matter
3. Physical matter
4. Physical matter
5. Chemical matter
6. Physical matter.
Answer:
A double bond between carbon atoms
Explanation:
The suffix -ene is used for alkenes, which tells you that the molecule has a carbon-carbon double bond.
16(2)/74.1=.431
.431x100= 43.1%
