Question

Identify each of the following compounds as a nonelectrolyte, a weak electrolyte, or a strong electrolyte: (a) ethanolamine \(\left(\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{ONH}_{2}\right),(\mathrm{b})\) potassium fluoride (KF), (c) ammonium nitrate ( \(\mathrm{NH}_{4} \mathrm{NO}_{3}\) ), (d) isopropanol \(\left(\mathrm{C}_{3} \mathrm{H}_{7} \mathrm{OH}\right)\)

Short answer

(a) Weak electrolyte, (b) Strong electrolyte, (c) Strong electrolyte, (d) Nonelectrolyte.

Step-by-step solution

Understand the Terms

Before identifying the compounds, understand that a nonelectrolyte does not dissociate into ions in water, a weak electrolyte partially dissociates, and a strong electrolyte completely dissociates into ions.

Determine Nature of Ethanolamine (C₂H₅ONH₂)

Ethanolamine is an organic amine, similar to alcohol in terms of ionization. It does not completely dissociate into ions in water, behaving as a weak base. Therefore, it is classified as a weak electrolyte.

Determine Nature of Potassium Fluoride (KF)

Potassium fluoride is an ionic compound composed of a metal (K) and a nonmetal (F). Ionic compounds typically dissociate completely in water, making potassium fluoride a strong electrolyte.

Determine Nature of Ammonium Nitrate (NH₄NO₃)

Ammonium nitrate is an ionic compound containing the cations and anions NH₄⁺ and NO₃⁻. Such compounds fully dissociate in aqueous solutions and are thus classified as strong electrolytes.

Determine Nature of Isopropanol (C₃H₇OH)

Isopropanol is an alcohol, which is generally a compound that does not dissociate into ions in solution. It therefore acts as a nonelectrolyte when dissolved in water.

Key concepts

Nonelectrolyte

A nonelectrolyte is a substance that, when dissolved in water, does not dissociate into ions. Therefore, it does not produce an electrically conductive solution. An example of a nonelectrolyte is isopropanol The important characteristics of nonelectrolytes include:

• No ion formation in solution
• Non-conductive
• Often covalent or organic compounds

When you dissolve isopropanol in water, it intermingles with the water molecules but does not dissociate into ions. This lack of dissociation is due to the strong O-H bonds within the molecule. This maintains the solution's lack of electrical conductivity, which differentiates nonelectrolytes from other electrolytic compounds.

Weak Electrolyte

Weak electrolytes only partially dissociate into ions in an aqueous solution. This partial dissociation means that their solutions conduct electricity but very poorly. Ethanolamine is a good example of a weak electrolyte. It is an organic amine, similar to an alcohol. When dissolved, it ionizes only slightly to form a small number of ions. Here are some key points about weak electrolytes:

• Partial ionization in solution
• Weak electrical conductivity
• Often weak acids or bases

The limited production of ions contributes to the low electrical conductivity in these solutions, giving weak electrolytes their distinguishing characteristics.

Strong Electrolyte

Strong electrolytes dissociate completely into ions when dissolved in water. As a result, they are excellent conductors of electricity in solution. Potassium fluoride (KF) is a strong electrolyte, fully breaking into potassium (K⁺) and fluoride (F⁻) ions. Strong electrolytes share these attributes:

• Complete ionization in solution
• Strong electrical conductivity
• Typically ionic compounds

These compounds form solutions that allow electric currents to pass through quite efficiently due to the presence of free-moving ions. This feature is what sets strong electrolytes apart from weak electrolytes and nonelectrolytes.

Ionic Compounds

Ionic compounds consist of metals and nonmetals bonded together by ionic bonds. In water, they tend to dissociate completely into their constituent ions. Ammonium nitrate is an example of an ionic compound. In aqueous solutions, it separates into ammonium (NH₄⁺) and nitrate (NO₃⁻) ions. Characteristics of ionic compounds include:

• Formation of positive and negative ions
• High solubility in water
• Good electrical conductivity

These compounds usually exhibit strong electrolytic behavior. The ability of ionic compounds to dissociate is what makes them effective in conducting electricity when dissolved in a solution.

Organic Compounds

Organic compounds primarily consist of carbon and hydrogen, often in combination with oxygen, nitrogen, and other elements. They encompass a wide variety of chemical substances, including alcohols and amines. Isopropanol and ethanolamine are examples of organic compounds. These compounds generally do not dissociate into ions and thus exhibit either weak or no electrolytic properties. Features of organic compounds include:

• Covalent bonding
• Low electrical conductivity in solution
• Diverse solubility profiles

Due to their lack of ion formation, most organic compounds act as nonelectrolytes or weak electrolytes. Hence, they do not conduct electricity effectively when dissolved in water.