Solutions, Electrolytes, and Chemical Reactions

Vocabulary flashcards covering solutions, electrolytes, solubility rules, precipitation, acid-base neutralizations, redox processes, oxidation numbers, molarity, and dilutions.

Solution

A homogeneous mixture composed of a solvent and one or more ($1+$) solutes.

Solvent

The liquid substance that other materials are dissolved into.

Solute

The substance or "things" that are dissolved in a solvent.

Electrolytes

Substances that dissociate into ions when dissolved in water.

Strong Electrolytes

Substances that dissociate completely into ions in solution, consisting of soluble ionic compounds, strong acids (e.g., $HCl$, $HBr$, $HI$, $HClO_4$, $HClO_3$, $H_2SO_4$, $HNO_3$), and strong bases (Group 1 hydroxides, $Ba(OH)_2$, $Sr(OH)_2$, $Ca(OH)_2$).

Weak Electrolytes

Substances that only partially dissociate into ions in solution, including weak acids (e.g., $HF$, $CH_3COOH$) and weak bases (e.g., $NH_3$, $CH_3NH_2$).

Nonelectrolytes

Substances that dissolve in water without dissociating into ions (e.g., $CH_3OH$, $C_6H_{12}O_6$).

Precipitation Reactions

Reactions in which two aqueous ($aq$) ionic solutions are mixed and react to form an insoluble solid called a precipitate.

Precipitate

An insoluble solid ($s$) that forms and separates out from a liquid solution during a precipitation reaction.

Spectator Ions

Ions that are present in a chemical reaction mixture but do not participate in the chemical change; they are canceled out when converting a complete ionic equation into a net ionic equation.

Net Ionic Equation

A chemical equation that shows only the participating species that form the product (such as an insoluble solid or water), omitting all spectator ions.

Acid

A chemical species that donates $H^+$ ions.

Base

A chemical species that accepts $H^+$ ions.

Neutralization

A common acid-base reaction that typically produces a salt and water: $\text{Acid} + \text{Base} \rightarrow \text{Salt} + \text{Water}$.

Acid + Carbonate Reaction

A special class of acid-base reaction that does not produce only salt and water, but also produces carbon dioxide gas ($CO_2$): $2HCl + Na_2CO_3 \rightarrow 2NaCl + H_2O + CO_2$.

Oxidation-Reduction (Redox) Reactions

Reactions that involve electrons being transferred or redistributed between substances through two simultaneous processes: oxidation and reduction.

Oxidation

The loss of one or more electrons by a substance during a reaction.

Reduction

The gain of one or more electrons by a substance during a reaction.

OIL RIG

A mnemonic device used to remember redox reactions: "Oxidation Is Loss, Reduction Is Gain" of electrons.

Oxidizing Agent

A substance that causes another substance to lose electrons (be oxidized), while it itself gets reduced.

Reducing Agent

A substance that causes another substance to gain electrons (be reduced), while it itself gets oxidized.

Oxidation Number

An assigned charge value for an atom determined by specific rules: $0$ for free elements; ion charge for monoatomic ions; $+1$ for Group 1 metals; $+2$ for Group 2 metals; $-2$ for oxygen; $+1$ for hydrogen; $-1$ for fluorine; summing to $0$ in neutral compounds and to the total charge in polyatomic ions.

Molarity

The concentration of a solution defined as the number of moles of solute dissolved in $1\text{ liter}$ of solution: $\text{Molarity} = \frac{\text{moles of solute}}{\text{liters of solution}}$.

Dilution

The procedure of preparing a less concentrated solution by taking an existing concentrated solution and adding solvent, calculated using the equation $M_1V_1 = M_2V_2$.

Dissociation

The process that occurs when a soluble ionic compound dissolves in water and its constituent ions separate.