Chapter 4: The Major Classes of Chemical Reactions

This set of vocabulary flashcards covers the major concepts of chemical reactions in aqueous solutions, including ionic equations, solubility rules, acid-base theories, titrations, and oxidation-reduction definitions.

Molecular equation

A chemical equation that shows all of the reactants and products as intact, undissociated compounds.

Total ionic equation

A chemical equation that shows all of the soluble ionic substances dissociated into ions.

Net ionic equation

A chemical equation that eliminates the spectator ions and shows the actual chemical change taking place.

Spectator ions

Ions that do not participate in the actual chemical change and are eliminated when writing a net ionic equation from a total ionic equation.

Precipitation reaction

A reaction in which an insoluble product, called a precipitate, forms when two aqueous solutions are mixed.

Acid (Arrhenius definition)

A substance that produces $H^+$ ions when dissociated in water.

Base (Arrhenius definition)

A substance that produces $OH^-$ ions when dissociated in water; strong bases may contain $OH^-$ or $O^{2-}$ as part of their structure.

Acid (Bronsted-Lowry definition)

A molecule or ion that donates a proton ($H^+$).

Base (Bronsted-Lowry definition)

A molecule or ion that accepts a proton ($H^+$).

Equivalence point

The point in a titration when all the moles of $H^+$ ions present have reacted with an equivalence number of moles of $OH^-$ ions added from the buret.

End point

The point in a titration when a tiny excess of titrant changes the indicator permanently to its color in base.

Standardized solution

A solution of known concentration used in a titration to determine the concentration of another solution.

Oxidation

The loss of electrons during a chemical reaction, resulting in an increase in oxidation number.

Reduction

The gain of electrons during a chemical reaction, resulting in a decrease in oxidation number.

Oxidizing agent

The species that undergoes reduction and performs the oxidation by gaining electrons.

Reducing agent

The species that undergoes oxidation and performs the reduction by losing electrons.

Oxidation number (O.N.)

The charge an atom would have if electrons were not shared but were transferred completely.

Combination reaction

A redox reaction that produces fewer products than reactants.

Decomposition reaction

A redox reaction that produces more products than reactants.

Displacement reaction

A reaction where the number of products equals the number of reactants, typically involving an element replacing another in a compound.

Activity series of the metals

A list of metals ranked according to their strength as reducing agents and their ability to displace $H_2$ from various sources.

Electrolytes

Substances such as acids and bases whose strength in aqueous solution is related to the degree to which they dissociate into ions.

Oxyacid

An acid whose acidity depends on the electronegativity of the central atom $Z$ in the structure $H-O-Z$, where higher electronegativity makes the proton more easily lost.