What is the difference between molecular and ionic compounds and how these groups of compounds are related to strong and weak electrolytes?

Answer 1

Ionic compounds are generally considered to be those that result from the combination of a metal and a non metal. Examples of this would be NaCl (Na is a metal, Cl is a non metal), CaBr₂ (Ca is a metal, Br is a non metal), Al₂S₃ (Al is a metal, S is a non metal).

Molecular compounds (also called covalent compounds) are generally considered to be those that result from the combination of two non metals or a metal and a metaloid and where the electrons are shared between to two elements. Examples might be CO₂, O₂, PCl₅, etc.

As far as strong and weak electrolytes are concerned, the ionic type of compounds are generally strong electrolytes because they dissociate completely in water and produce their respective ions which are then capable of conducting an electric current. Molecular compounds are generally weak or non electrolytes because they ionize only slightly or not at all and therefore are not able to conduct an electric current.