Primary amines can be prepared from alkyl halides through nucleophilic substitution reactions with ammonia.

PCl5 is commonly used to convert alcohols into alkyl halides through a substitution reaction.

An acid chloride is used to convert an amine to an amide through acylation.

Solids generally have the highest density due to closely packed particles.

The cubic crystal system has the highest symmetry among all crystal systems.

Molecular solids are composed of molecules held together by van der Waals forces and have a definite melting point.

Crystalline solids have a definite melting point due to their ordered structure, unlike amorphous solids which melt over a range of temperatures.

Vitamin B1 (thiamine) acts as a coenzyme in carbohydrate metabolism.

Vitamin K is essential for the synthesis of proteins required for blood clotting.

Vitamin B1 (thiamine) acts as a coenzyme in the metabolism of carbohydrates.

Vitamin A is essential for the formation of rhodopsin, a pigment in the retina that is crucial for vision.

Vitamin C is abundant in citrus fruits like oranges, lemons, and grapefruits.