Answer:
A and C represent elements while B and D represent Compounds
Explanation:
chemical elements cannot be broken down into simpler substances by any chemical reaction. While A chemical compound is a chemical substance composed of many identical molecules composed of atoms from more than one element held together by chemical bonds
Basic because a pH greater than 7 is basic
That is called condensation
Answer: Option (B) is the correct answer.
Explanation:
A molecules that will have more number of hydrogen bonding will has highest boiling point because to break the hydrogen bonds high heat needs to be provided.
So, in the molecule 
there is presence of two alcoholic groups. Hence, it will have strongest hydrogen bonding as compared to the rest of molecules.
In the molecule 
there will be hydrogen bonding and dipole-dipole interactions. Hence, it boiling point will be slightly less than .
In the molecule 
, there will be only hydrogen bonding. Hence, its boiling point is less than .
In the molecule 
, there is no hydrogen bonding but there will be only dipole-dipole interactions. Hence, its boiling point will be the least.
Therefore, we can conclude that increasing order of boiling point will be as follows.
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