Question

Classify each of the following substances and descriptions as an electrolyte or a nonelectrolyte. Note: If any part of this question is answered incorrectly, a single red X will appear indicating that one or more substances have been placed incorrectly.

-most molecular solutes

-sodium chloride, NaCl

-potassium iodine, KI

-table sugar

-methanol, CH3OH

-sodium hydroxide, NaOH

-a substance that forms an aqueous solution that does not conduct electricity

-a soluble ionic compound

Answer 1

Concepts and reason

Substances are classified into electrolytes and non-electrolytes on the basis of their behavior in solution.

Fundamentals

Electrolytes are the substances which get dissociated in solution and conduct electricity.

Non-electrolytes are the substances which do not get dissociated in solution.

The compounds with ionic bond are Sodium chloride $\left( {{\rm{NaCl}}} \right)$ , Potassium iodine $\left( {{\rm{KI}}} \right)$ , Sodium hydroxide $\left( {{\rm{NaOH}}} \right)$ and ‘A soluble ionic compound’.

The compounds with covalent bonds are Table sugar and Methanol $\left( {{\rm{C}}{{\rm{H}}_{\rm{3}}}{\rm{OH}}} \right)$

The compound with molecular bond is ‘Most molecular solutes’.

‘A substance that forms aqueous solution that does not conduct electricity’ is either covalent or molecular.

The nature of substances is assigned as Most molecular solutes are non-electrolyte, Sodium chloride $\left( {{\rm{NaCl}}} \right)$ is electrolyte, Potassium iodine $\left( {{\rm{KI}}} \right)$ is electrolyte, Table sugar is non-electrolyte, Methanol $\left( {{\rm{C}}{{\rm{H}}_{\rm{3}}}{\rm{OH}}} \right)$ is non-electrolyte, Sodium hydroxide $\left( {{\rm{NaOH}}} \right)$ is electrolyte, A substance that forms aqueous solution that does not conduct electricity is non-electrolyte and A soluble ionic compound is electrolyte.

Ans:

Most molecular solutes: non-electrolyte

Sodium chloride, NaCl: electrolyte

Potassium iodine, ${\rm{KI}}$ : electrolyte

Table sugar: non-electrolyte

Methanol, ${\rm{C}}{{\rm{H}}_{\rm{3}}}{\rm{OH}}$ : non-electrolyte

Sodium hydroxide, ${\rm{NaOH}}$ : electrolyte

A substance that forms aqueous solution that does not conduct electricity: non-electrolyte

A soluble ionic compound: electrolyte