Introduction to Acids, Bases, pH, Buffers, and Carbon Chemistry

Vocabulary flashcards covering key topics from the lecture transcript including acids, bases, pH calculations, buffer systems, and carbon bonding properties.

Acid

A substance or solute that increases the $H^+$ ion concentration of a solution when added to it.

Base

A substance that decreases the $H^+$ ion concentration or breaks apart to yield hydroxide ions ($OH^-$) in solution.

Strong Acid

An acid that breaks apart completely (100\text{\text{%}}) into its individual ions when dissolved in liquid water, such as hydrochloric acid ($HCl$).

Strong Base

A base that breaks apart completely (100\text{\text{%}}) into its individual ions when dissolved in liquid water, such as sodium hydroxide.

Weak Acid

An acid in which less than 100\text{\text{%}}) of the molecules break apart into individual ions when dissolved in liquid water, allowing it to reversibly donate and accept back $H^+$ ions (e.g., carbonic acid, $H_2CO_3$).

Aqueous Solution

A solution that uses water as the solvent.

pH of a Solution

The negative logarithm of the $H^+$ ion concentration within a solution, calculated as $pH = -\text{log}[H^+]$.

Ion Product of Water at $25\text{ }^\text{o}\text{C}$

In pure water at $25\text{ }^\text{o}\text{C}$, the product of the molar concentrations of $H^+$ ions and $OH^-$ ions always equals $10^{-14}$.

Buffer

A solution or substance that prevents large changes in $pH$ by maintaining the $H^+$ and $OH^-$ ion concentrations.

Bicarbonate Buffer System

A buffer system composed of weak carbonic acid ($H_2CO_3$) and its conjugate base ($HCO_3^-$) that counteracts shifts in $pH$ by absorbing or releasing $H^+$ ions.

Organic Chemistry

The study of carbon-containing compounds, which generally contain one or more carbon-hydrogen bonds.

Valence

The number of unpaired electrons in an atom's valence shell, which determines the number of covalent bonds the atom can form with neighboring atoms.

Tetrahedral Shape

The three-dimensional arrangement formed around a carbon atom when it is covalently bonded to four different atoms.

Ethene

A molecule containing a carbon-carbon double bond, causing the joined carbon and hydrogen atoms to reside within the same three-dimensional plane.

Human Blood pH

The typical, slightly basic $pH$ of human blood, which is roughly $7.4$.