Question

Covalent compounds are usually water soluble.
(A) True
(B) False

Answer 1

Hint: Water is a polar molecule that means charge is unevenly distributed in the water molecule due to the electronegativity of oxygen so in order to dissolve in polar molecules compound has to be polar as well so we will check the polarity of covalent compounds and check whether the statement is true or false.

Complete answer:
- Covalent compounds are formed via covalent bonding between a metal and a non-metal.The intramolecular bonding between them is strong because the atoms are held very strongly together. As a result of this, bond between covalent compounds tends to be weak.
- A covalent bond between two atoms is formed by equal sharing of electrons from both atoms. The pair of electrons which participates in bonding is called a shared pair or bonding pair. The sharing of electrons can be done between the same kind of atoms or between different kinds of atoms.
- The melting and boiling points of covalent compounds are generally low because of the weak force of attraction between them.
- When covalent compounds are dissolved in water they dissociate into molecules, but not into ions. Water is a polar solvent, but covalent compounds are nonpolar. This implies that covalent compounds don't dissolve in water and make a separate layer on the surface of the water.
Hence we can say that covalent compounds are insoluble in water.

Therefore, the given statement is false and option (B) is correct.

Note:
Due to absence of charged ions, Covalent compounds are poor conductors of electricity. Graphite is an exception though. They are also bad conductors of heat as their molecules don’t have free electrons.