Which of the following are the general properties of the "Ionic compounds"?
(A) Generally brittle and break into pieces when pressure is applied.
(B) Have high melting and boiling points.
(C) Conduct electricity in the molten state.
(D) Generally soluble in solvents like kerosene and petrol but insoluble in water.
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → (A), (B) and (C) only
Ionic compounds, such as sodium chloride, are made of positive and negative ions held by strong electrostatic forces in a regular crystal. Their properties follow from these strong forces and from the ions.
(A) Generally brittle and break into pieces when pressure is applied. Correct. Pressure shifts the layers of ions so that like charges come side by side and repel, and the crystal breaks.
(B) Have high melting and boiling points. Correct. A lot of energy is needed to overcome the strong attraction between the ions.
(C) Conduct electricity in the molten state. Correct. On melting, the ions become free to move and carry the current; in the solid they are fixed in place.
(D) Generally soluble in solvents like kerosene and petrol but insoluble in water. Incorrect. It is the other way round: ionic compounds are generally soluble in water and insoluble in kerosene and petrol.