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)
Global Warming has been increased by living organisms like animals and humans by many ways:
1) We burn fossil fuels, which is very bad for our Environment's health
2) Animals like cows & buffalo produces a lot of methane which causes Global Warming.
3) Animals cut a lot of trees for their products, so increase the amount of Carbon dioxide in the atmosphere, thus increases Global Warming.
4) We don't minimize our dependence on Non-renewable source of energy which 'causes a lot of pollution in the environment
Hope this helps!
Answer:
Since they're easy to separate, covalent compounds have low melting and boiling points. 2) Covalent compounds are soft and squishy (compared to ionic compounds, anyway). The reason for this is similar to the reason that covalent compounds have low melting and boiling points. When you hit an ionic compound with something, it feels very hard
Explanation:
mark brainliest plz
Answer:

Explanation:
The given reactions are:
PbCl2(aq)⇌Pb2+(aq)+2Cl−(aq) 
AgCl(aq)⇌Ag+(aq)+Cl−(aq) 
Required reaction is:
PbCl2(aq)+2Ag+(aq)⇌2AgCl(aq)+Pb2+(aq)
