Question

Why are ionic compounds usually hard? how is it that ionic compounds in the solid state do not conduct electricity but they do so when in molten state? on additing dilute hcl acid to copper oxide powder the solution formed is blue green predict the new compound formed which impart a blue green colour to the solution​

Answer 1

Answer:

The ionic compounds are usually hard because the ions are held by strong electrostatic force of attraction as the positive and negative ions are strongly attracted to each other and difficult to separate them apart. Ionic compounds conduct electricity when molten(liquid) or in aqueous solution(dissolved in water) because their ions are free to move from place to place. Ionic compounds cannot conduct electricity when solid as their ions are held in fixed positions and cannot move.