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)
Answer:
No net change in reaction occurs in this nucleophilic acyl subtitution reaction
Explanation:
Sodium ethoxide in ethanol gives nucleophilic acyl substitution reaction with ethyl-2-methylpropanoate.
Here ethoxide group replaces an ethoxide group from ester through addition-ellimination pathway.
So, ultimately, the product of this reaction is identical with reactant i.e. ethyl-2-methylpropanoate is reproduced.
Hence one might observe no change during reaction as product and reactant of this reaction are same.
Mechanistic pathway has been shown below.
Answer:
The answer is B
B) gravitational potential energy only