Question

Ions that do not directly participate in a reaction in solution are called ______ ions.

Short answer

The ions that do not directly participate in a reaction in solution are called \(\textbf{spectator ions}\).

Step-by-step solution

Recall the related term in chemistry

The term we need to define is related to ions that do not directly participate in a chemical reaction in solutions. These ions are commonly known as spectator ions.

Answer

The correct term to fill in the blank is: spectator ions.

Key concepts

Ions in Solution

When substances dissolve in water, they break down into smaller particles known as ions. This process is called dissociation.
For instance, when table salt (NaCl) dissolves in water, it separates into sodium ions (Na⁺) and chloride ions (Cl⁻). These ions can move freely in solution, allowing them to interact with other ions or molecules.
In a solution, you can find both positive ions, called cations, and negative ions, called anions. The total charge in a neutral solution is balanced because the sum of the positive charges equals the sum of the negative charges. The ions that actually participate in reactions are called reactive ions, while those that do not participate directly are known as spectator ions.

Chemical Reactions

Chemical reactions in solutions often involve ions combining to form new products.
For example, when mixing solutions of silver nitrate (AgNO₃) and sodium chloride (NaCl), the silver ions (Ag⁺) react with chloride ions (Cl⁻) to form a precipitate, silver chloride (AgCl). This is an example of a chemical change where the original ions combine to form a new, insoluble compound.
In this reaction, other ions present in the solution, like sodium ions (Na⁺) and nitrate ions (NO₃⁻), do not participate directly in forming the product and remain in the solution. These ions are spectator ions because they simply "watch" the reaction happen without getting involved.

Solution Chemistry

Solution chemistry focuses on the interactions between solvents and solutes within a solution.
In aqueous solutions, water is the solvent that dissolves various solutes, which can include different ionic compounds. Understanding how these interactions occur helps in predicting the behavior of ions and molecules in the solution.
Solutions can undergo changes when mixed, which is what happens in many chemical reactions. For practical applications, chemists need to know which ions are reactive and which are spectator ions. This knowledge helps in designing chemical processes and predicting the outcomes of reactions.