Acids, Bases, and Titrations Lecture Notes

Flashcards covering the definitions, properties, and theories of acids and bases, as well as the procedures and equipment used in titrations.

Acid (General Properties)

Substances that taste tart or sour, act as electrolytes, change the color of indicators, and react with metals to form hydrogen gas.

Base (General Properties)

Substances that taste bitter, feel slippery (like soap), act as electrolytes, and are often found in cleaning agents like ammonia and bleach.

pH Scale

A scale used to measure acidity or basicity, ranging from $1$ to $14$. Acids have a pH from $1$ to $6.9$, while bases have a pH from $7.1$ to $14$.

Neutral

A substance with a pH of exactly $7$, such as pure water ($H_2O$).

Electrolyte

A compound that breaks its crystal lattice when dissolved in water and becomes a good conductor of electricity; both acids and bases function as these.

Neutralization Reaction

A reaction in which an acid and a base react in an aqueous solution to produce a salt and water.

Arrhenius Acid

A hydrogen-containing compound that ionizes to yield hydrogen ions ($H^+$) in aqueous solutions.

Arrhenius Base

A compound that ionizes to yield hydroxide ions ($OH^-$) in aqueous solutions.

Monoprotic Acid

An acid that contains one ionizable hydrogen, such as hydrochloric acid ($HCl$) or nitric acid ($HNO_3$).

Diprotic Acid

An acid that contains two ionizable hydrogens, such as sulfuric acid ($H_2SO_4$) or carbonic acid ($H_2CO_3$).

Triprotic Acid

An acid that contains three ionizable hydrogens, such as phosphoric acid ($H_3P O_4$).

Bronsted-Lowry Acid

A substance defined as a hydrogen ion ($H^+$) donor.

Bronsted-Lowry Base

A substance defined as a hydrogen ion ($H^+$) acceptor.

Conjugate Acid

The particle formed when a base gains a hydrogen ion ($H^+$).

Conjugate Base

The particle that remains after an acid has donated a hydrogen ion ($H^+$).

Lewis Acid

A substance that can accept a pair of electrons during a reaction.

Lewis Base

A substance that can donate a pair of electrons during a reaction.

Proton

A term used interchangeably with the hydrogen ion ($H^+$) because a hydrogen atom that loses its one electron consists only of a single proton in its nucleus.

Neutralization Equation

A modified molarity equation used to find neutrality: $\frac{M_1 V_1}{n_1} = \frac{M_2 V_2}{n_2}$, where $n$ represents the mole ratios (coefficients) from a balanced chemical reaction.

Titration

The process of adding a known amount of solution of known concentration (titrant) to determine the concentration of an unknown solution (analyte or titrand).

Titrant

The chemical with a known concentration that is added from a burette during a titration.

Analyte (Titrand)

The solution of unknown concentration that is being analyzed in a titration, typically held in an Erlenmeyer flask.

Burette

A long, narrow, graduated tube with a stopcock used to regulate the flow of titrant in a titration.

Stopcock

The valve at the bottom of a burette used to control the flow of liquid.

Meniscus

The concave curve formed by the surface of a liquid in a container; measurements should be read from the bottom of this curve at eye level.

Indicator

A substance added to the analyte that changes color to mark the endpoint of a titration, such as phenolphthalein turning pink.

Endpoint

The point in a titration where the indicator changes color, signaling that the amount of titrant added has neutralized the analyte.