General Chemistry: Limiting Reactants, Redox Reactions, Aqueous Stoichiometry, and Titrations

Comprehensive vocabulary flashcards covering limiting reactants, yields, redox reactions, solution properties, concentration units, and titrations from Basic Chemistry 1.

Limiting Reactant

The reactant that is completely consumed before the others in a chemical reaction, which controls the amount of products formed.

Excess Reactant

A reactant which is present in a larger quantity than needed to react with the amount of the limiting reactant, leaving an unreacted amount when the reaction ends.

Theoretical Yield

The maximum amount of product that would form if all of the limiting reagent reacted (as predicted by the balanced chemical equation)

Actual Yield

The quantity of product that is actually produced, and measured in an experiment

Percentage Yield

The ratio comparing the amount actually obtained to the theoretical maximum possible amount:

$$\text{Percentage Yield} = \frac{\text{Actual Yield}}{\text{Theoretical Yield}} \times 100$$

Oxidation

Loss of electrons

Gain of oxygen

Increase in oxidation number

Reduction

Gain of electrons

Loss of oxygen

Decrease in oxidation number

Oxidation Number

Number of electrons gained or lost during an oxidation-reduction reaction.

Displacement Reaction

A reaction in which an ion in solution is displaced (replaced) through the oxidation of an element (such as an elemental metal).

Half-Reaction Method

A method for balancing oxidation-reduction equations by treating the oxidation and reduction as two separate processes, balancing them individually, and combining them into an overall balanced equation.

Solution

A homogeneous mixture composed of two or more pure substances in a single phase.

Solvent

The component of a solution that is present in the greatest abundance.

Solute

Any substance dissolved in the solvent to form a solution.

Aqueous Solution

A solution in which water acts as the dissolving medium (solvent).

Electrolyte

A substance that, when dissolved in water, produces ions and results in a solution that conducts electricity.

Nonelectrolyte

A substance that dissolves in water without forming ions, producing a solution that does not conduct electricity.

Solvation

The process where solvent molecules (such as $H_2O$) separate, surround, and uniformly disperse solute ions into the liquid.

Precipitate

An insoluble solid that separates from an aqueous solution during a precipitation reaction.

Solubility

The maximum amount of solute that will dissolve in a given quantity of solvent at a specific temperature.

Arrhenius Acid

A substance that increases the concentration of hydrogen ions ($H^+$) when dissolved in water.

Arrhenius Base

A substance that increases the concentration of hydroxide ions ($OH^-$) when dissolved in water.

Brønsted-Lowry Acid

A substance that acts as a proton ($H^+$) donor.

Brønsted-Lowry Base

A substance that acts as a proton ($H^+$) acceptor.

Neutralization Reaction

A chemical reaction that occurs when a solution of an acid and a solution of a base are mixed, typically producing water and a salt.

Molarity ($M$)

A measure of concentration defined as:

no of moles of solute ÷ volume of the solution (in ltrs)

$$\text{Molarity }(M)=\frac{n\text{ (mol)}}{Volume\text{ (L)}}$$

Stock Solution

A routinely stored solution prepared or purchased in a concentrated form that is diluted prior to experimental use.

Dilution

The laboratory procedure for preparing a less concentrated solution from a more concentrated stock solution by adding solvent.

Molality ($m$)

A concentration unit defined as:

no of moles of solute ÷ mass of solvent (kg)

$$\text{Molality }(m)=\frac{n\text{ (mol)}}{\text{Mass of solvent (kg)}}$$

Mole Fraction ($\mathrm{X}$)

The ratio of:

no of moles of a specific component : total no of moles of all substances present in the mixture

Percentage by Mass (% w/w)

The percentage of a specific solute's mass in a solution or mixture

$$\text{\% } w/w = \frac{\text{Mass of solute}}{\text{Mass of solution}} \times 100\%$$

Percentage by Volume (% V/V)

A concentration expression based on the volumes of liquid solute and solution:

$$\text{\% } V/V = \frac{\text{Volume of solute}}{\text{Volume of solution}} \times 100\%$$

Percentage by Mass/Volume (% w/V)

The percentage of the mass of solute in grams per volume of solution in cm³:

$$\text{\% }w/V\left(\operatorname{cm}^3\right)=\frac{\text{Mass of solute (g)}}{\text{Volume of solution (cm}^3\text{)}}\times100\%$$

Gravimetric Analysis

An analytical technique based on the measurement of mass, commonly involving the formation, isolation, and weighing of a precipitate.

Titration

An analytical volumetric technique in which a solution of accurately known concentration is added gradually to a solution of unknown concentration until the chemical reaction is complete.

Standard Solution

A solution whose concentration is accurately and precisely known, used in titrations to determine the concentration of an analyte.

Titrant

The reagent solution of known concentration that is placed in a burette and delivered during a titration.

Analyte

The chemical substance or solution of unknown concentration placed in the receiving flask to be analyzed during a titration.

Equivalence Point

The point in a titration when the amount of titrant added is stoichiometrically equivalent to the amount of substance present in the analyte.

Redox Titration

A titration based on an oxidation-reduction reaction where an oxidizing agent is titrated against a reducing agent until complete electron transfer is achieved.