Acids, Bases and Salts Vocabulary Flashcards

Vocabulary practice flashcards covering definitions, classifications, theories, indicators, pH scale, acid rain, and salt preparation methods from Chapter 3-A: Acids, Bases and Salts.

Acid

A compound which, when dissolved in water, yields hydronium ions ($H_3O^+$) as the only positively charged ions.

Base

A compound, usually an oxide or hydroxide of a metal (including ammonium hydroxide), which reacts with hydronium ions of an acid to give salt and water only.

Alkali

A base compound soluble in water which, when dissolved in water, yields hydroxyl ions ($OH^-$) as the only negatively charged ions.

Organic Acids

Acids derived from plants, such as citric acid, oxalic acid, tartaric acid, and acetic acid.

Inorganic Acids

Acids derived from minerals (also called mineral acids), such as hydrochloric acid ($HCl$), sulphuric acid ($H_2SO_4$), and nitric acid ($HNO_3$).

Hydracids

Acids containing hydrogen and a non-metallic element other than oxygen, such as $HCl$, $HBr$, and $HI$.

Oxyacids

Acids containing hydrogen, another element, and oxygen, such as nitric acid ($HNO_3$) and sulphuric acid ($H_2SO_4$).

Strong Acid

An acid that dissociates almost completely in aqueous solution, thereby producing a high concentration of hydrogen ($H^+$) or hydronium ($H_3O^+$) ions.

Weak Acid

An acid that dissociates only partially in aqueous solution, thereby producing a low concentration of hydrogen ($H^+$) or hydronium ($H_3O^+$) ions.

Glacial Acetic Acid

Anhydrous acetic acid that forms crystals upon cooling.

Strong Alkali

An alkali that dissociates almost completely in aqueous solution, thereby producing a high concentration of hydroxyl ($OH^-$) ions.

Weak Alkali

An alkali that dissociates only partially in aqueous solution, thereby producing a low concentration of hydroxyl ($OH^-$) ions.

Basicity of Acids

The number of hydrogen ions ($H^+$) that can be produced per molecule of the acid in aqueous solution, or the number of hydroxyl ions with which one molecule of an acid combines.

Acidity of Bases

The number of hydroxyl ions ($OH^-$) that can be produced per molecule of the base in aqueous solution, or the number of hydrogen ions with which a molecule of a base combines.

Monobasic Acid

An acid that ionizes in aqueous solution to produce one hydrogen ion per molecule of the acid and dissociates in one step.

Dibasic Acid

An acid that ionizes in aqueous solution to produce two hydrogen ions per molecule of the acid and dissociates in two steps.

Tribasic Acid

An acid that ionizes in aqueous solution to produce three hydrogen ions per molecule of the acid and dissociates in three steps.

Arrhenius Theory

Theory stating that acids are substances that dissociate in aqueous solution to give hydrogen ($H^+$) ions.

Lowry-Bronsted's Theory

Theory stating that acids are proton donors and bases are proton acceptors, where a proton is defined as $H^+$.

Coordinate Covalent Bond

The bond formed between the atom of a polar covalent molecule with a lone pair of electrons and an ion which accepts the lone pair of electrons.

Neutralization (Ionic Theory)

The process due to which $H^+$ ions of an acid combine completely with $OH^-$ ions of a base to yield salt and water only ($H^+_{(aq)} + OH^-_{(aq)} \rightarrow H_2O_{(l)}$).

Heat of Neutralization

The amount of heat liberated when $1\,\text{gram equivalent}$ of an acid or a base is completely neutralized.

Acid Rain

Rain or precipitation acidic in nature with a $pH$ less than $5.6$, consisting of a complex mixture of sulphuric acid ($H_2SO_4$), sulphurous acid ($H_2SO_3$), nitric acid ($HNO_3$), and nitrous acid ($HNO_2$).

Indicators

Weak organic compounds (acids or bases) which change colour in accordance with the $pH$ of the solution.

Ionic Product of Water ($K_w$)

The product of the hydrogen ion and hydroxyl ion concentrations in pure water, equal to $[H^+][OH^-] = 10^{-14}$ at $25\,^\circ\text{C}$.

pH Value

The negative logarithm (to the base 10) of the hydrogen ion concentration expressed in moles per litre ($pH = -\log_{10}[H^+]$).

Universal Indicator

A mixture of organic dyes or mixed indicators (such as $pH$ paper or solution) that indicates the strength or $pH$ range of an acidic or alkaline solution by producing different colours across different $pH$ values from $0$ to $14$.

Salt

An ionic compound formed by the partial or complete replacement of the replaceable hydrogen ion of an acid by a metallic or ammonium ion, yielding positive ions other than $H^+$ and negative ions other than $OH^-$ on dissociation.

Acid Salt

A salt formed by partial replacement of the replaceable hydrogen ions of an acid molecule by a basic radical, containing replaceable hydrogen atoms and exhibiting acidic properties in solution.

Normal Salt

A salt formed by complete replacement of the replaceable hydrogen ions of an acid molecule by a basic radical, containing no replaceable hydrogen atoms in its molecule.

Basic Salt

A salt formed by partial replacement of hydroxyl radicals of a diacidic or triacidic base with an acid radical, containing a metallic cation, a hydroxyl ion, and an acid anion.

Double Salt

A salt formed by mixing saturated solutions of two simple salts followed by crystallization, containing a mixture of two simple salts chemically combined.

Mixed Salt

A salt containing two or more basic radicals or acid radicals, such as sodium potassium carbonate ($NaKCO_3$) or bleaching powder ($Ca(OCl)Cl$).

Complex Salt

A salt formed by mixing saturated solutions of simple salts followed by crystallization, which on dissociation yields a simple ion and a complex ion.

Direct Combination (Synthesis)

A method of preparing binary salts by directly reacting a metallic element with a non-metallic element (e.g., $2Fe + 3Cl_2 \rightarrow 2FeCl_3$).

Precipitation (Double Decomposition)

A method of preparing insoluble salts by combining two soluble salt solutions to yield a precipitated insoluble salt and a soluble salt.

Titration

A neutralization method involving a soluble base (alkali) and a dilute acid used to prepare soluble salts of potassium, sodium, or ammonium.