The most common pairing would be sodium forming an ion after transfering an electron to chlorine
Nitrogen makes up around 78% of the total atmosphere.
Answer: B. It is an ether because it is unable to to form a hydrogen bond, so it is less soluble than water
Explanation: Alcohols are more soluble in water as they can form hydrogen bonding with water whereas ethers are less soluble as they do not form hydrogen bonds with water.
For formation of hydrogen bond, the electronegative atom (F, Oand N) must be attached to hydrogen and in ethers (ROR), there is no hydrogen directly attached to electronegative oxygen atom, thus are less soluble in water.