Answer:
The ancient Greeks believed in the four elements of air, earth, fire, and water. The Greek philosopher Empedocles is known for originating the theory of these classic four elements being the basis of all things.
The correct option is D.
The hydrogen atoms that are attached to the nitrogen atom in the ammonia molecule are capable of forming hydrogen bond. The hydrogen bond that exist in the ammonia molecule is the reason why it shows higher boiling point compare to the other hydrides. Hydrogen bond occur in ammonia because ammonia is one of the most electronegative elements.
Answer:
The correct answer is B) electronegativities of the bonded atoms in a molecule of the compound .
Explanation:
When two atoms forming a bond differ in their electronegativities at that time bond polarity is generated
In simple words a bond will be polar when the bonding electrons are not equally shared by two atoms.As a result the atom attract the bonding electron pair towards itself gain partial negative charge and the other atom gains partial positive charge.
For HCl is a polar compound because H and Cl atom differ in their electronegativities,as a result the bonding electron pair is not shared equally by H and Cl atoms.