Determination of pH and Titration

Comprehensive vocabulary and core concepts from the lecture on pH determination and the titration process, including acid-base theories and strong acid/base classifications.

Acidus

The Latin word for "sour," which was first associated with the taste of citrus fruits and is the root of the word "acid."

Arrhenius Acid

A substance that produces hydronium ion ($H_3O^+$ , also simplified as $H^+$) in water, according to Svante Arrhenius.

Arrhenius Base

A substance that produces hydroxide ion ($OH^-$) in water, according to Svante Arrhenius.

Brønsted-Lowry Acid

A substance that donates a proton ($H^+$), as classified by Nicolaus Brønsted and Martin Lowry.

Brønsted-Lowry Base

A substance that accepts a proton ($H^+$), as classified by Nicolaus Brønsted and Martin Lowry.

Conjugate base

The species that remains when a proton is transferred from the acid.

Conjugate acid

The species formed when a proton is transferred to the base.

Lewis Acid

A substance that accepts an electron pair, as classified by Gilbert Lewis.

Lewis Base

A substance that donates an electron pair, as classified by Gilbert Lewis.

Electrophile

An electron or negative "loving" species.

Nucleophile

A positive "loving" species.

Autoionization of water

The phenomenon where water has the ability to act like both an acid and a base.

Strong Acids and Bases

Species that completely dissociate to form ions in a solution.

Dissociation reaction

A chemical reaction in which a compound breaks apart into two or more components, represented as $AB \rightarrow A + B$.

6 Strong Acids

$HClO_4$ (perchloric acid), $HCl$ (hydrochloric acid), $HBr$ (hydrobromic acid), $HI$ (hydroiodic acid), $HNO_3$ (nitric acid), and $H_2SO_4$ (sulfuric acid).

6 Strong Bases

$LiOH$ (lithium hydroxide), $NaOH$ (sodium hydroxide), $KOH$ (potassium hydroxide), $Ca(OH)_2$ (calcium hydroxide), $Sr(OH)_2$ (strontium hydroxide), and $Ba(OH)_2$ (barium hydroxide).

pH (Potential of Hydrogen)

A measure of the acidity or basicity of an aqueous solution calculated using the Hydronium Ion concentration ($[H^+]$).

Neutral pH

A pH value of exactly $7$.

Acidic pH Range

A pH value below $7$, ranging down to $0$.

Basic pH Range

A pH value above $7$, ranging up to $14$.

pH Formula

$$pH = -\log(H^+)$$

pOH Formula

$$pOH = -\log(OH^-)$$

Relationship between pH and pOH

$$pH + pOH = 14$$

Titration

A process carried out to determine the concentration of a particular solute in a solution by combining a solution of unknown concentration with a reagent of known concentration.

Standard Solution/Titrant

The solution of known concentration in a titration.

Titrand/Analyte

The solution of unknown concentration in a titration.

Equivalence Point

The point at which stoichiometrically equivalent quantities are brought together during titration.

Indicator

A substance that changes color at or near the equivalence point.

Phenolphthalein

An indicator that is colorless in acidic solution and pink in basic solution, with a pH range of $8.2 - 10.0$.

Molarity Formula

$$\text{Molarity} = \frac{\text{amount of solute in moles (n)}}{\text{volume of solution in liters (L)}}$$

Titration Stoichiometry Formula

$n_{base} \times M_{acid} \times V_{acid} = n_{acid} \times M_{base} \times V_{base}$, where $n$ represents the coefficients from the balanced equation.