Question

Strong electrolytes are those which:
(A) dissolve readily in water
(B) conduct electricity
(C) dissociate into ions at high dilution
(D) completely dissociate into ions at all dilutions

Answer 1

Electrolytes are those substances that give ion when dissolved in water. The classification of electrolytes is based on their ability to dissociate in solutions and thus by knowing the differences between strong and weak electrolytes we could arrive at the answer.

Complete step by step solution:
- Let's start with the concept of electrolytes. As we know electrolytes are those chemicals which break into ions in water. It can also be described as those substances when dissolved in a polar solvent produces an electrically conducting solution.
-We can classify the electrolytes into two categories on the basis of degree of dissociation of ions in solutions and they are strong electrolytes and weak electrolytes.
- In strong electrolytes, the electrolyte gets completely dissociated into ions in the solution. As a result the solution will contain no molecules of the electrolyte and only ions will be present. They are usually good conductors of electricity, but only in molten form or aqueous solutions.
- The general equation for the dissociation of a strong electrolyte can be written as follows
$Strong\text{ }electrolyte{{e}_{(aq)}}\to Catio{{n}^{+}}_{(aq)}+Anio{{n}_{(aq)}}^{-}$
- Strong base, strong acids and ionic salts which are not weak acids or bases are usually considered as strong electrolytes. The main examples of strong electrolytes are sodium hydroxide, hydrochloric acid, sulphuric acid, potassium hydroxide etc.
- As we have seen, in strong electrolytes they consist of cations and anions and hence they are able to conduct electricity. From the definition of strong electrolytes, it's clear that they dissolve readily in water and completely dissociate into ions at all dilutions. Hence options (A), (B) and (D) represents the properties of a strong electrolyte.

Therefore, the answers are options (A), (B) and (D).

Note: It should be noted that in weak electrolytes dissociation is up to a small extent and hence they are partially ionized. Thus, dissociation of ion at high dilutions is the property of weak electrolytes whereas the dissociation of ions of strong electrolytes takes place at all dilutions. Hence the option (C) is a property which belongs to weak electrolytes.