Name: stepwise ionization of polyprotic acids
Uploaded: 2020-09-24T15:06:51.000Z
Duration: 3 min 38 s
Channel: JoVE

K12 Standards

north-carolina-k-12-science-standard-course-of-study

North Carolina K-12 Science Standard Course of Study

9-12

Physical Science

Matter and its Interactions

PS.PSc.2.5

Polyprotic Acids

Kwasy monoprotonowe, podobnie jak kwas fluorowodorowy, zawierają pojedynczy jonizowalny proton. Natomiast kwasy poliprotonowe zawierają dwa lub więcej jonizowalnych protonów. Na przykład kwas siarkowy ma dwa jonizowalne protony, a kwas fosforowy ma trzy.
Kwas poliprotonowy traci kolejno każdy ze swoich protonów, a każda reakcja ma swoje własne Kaa.
Łatwiej jest usunąć proton z obojętnej cząsteczki niż z cząsteczki naładowanej ujemnie, ponieważ ładunek ujemny zwiększa siłę wiązania między protonem a anionem.
Dlatego dla kwasu fosforowego Ka do usuwania pierwszego protonu, Ka1, jest wyższy niż drugi proton, Ka2, który jest wyższy niż Ka3.
pH kwasu poliprotonowego można oszacować tylko przy użyciu pierwszej reakcji, jeśli Ka1 jest co najmniej tysiąc razy większe niż jego kolejne Kára.
Na przykład pH 0,050 molowego roztworu kwasu askorbinowego można określić za pomocą jego Ka1 i tabeli ICE.
Po rozpuszczeniu w wodzie kwas askorbinowy dysocjuje na jony hydroniowe i askorbinianowe. Ka1 dla tej reakcji wynosi 8 × 10−5 i jest równe stężeniu hydronimu pomnożonemu stężeniu monoanionu askorbinianu podzielonemu przez stężenie kwasu askorbinowego.
Dla tej reakcji można przygotować tabelę ICE ze stężeniami początkowymi i równowagowymi. Ze względu na małą wartość x, 0,050 minus x jest w przybliżeniu równe 0,050.
Podstawiając te wartości do wyrażenia dla Ka1, wartość x jest równa 0,0020 mola, co stanowi tylko 4% początkowego stężenia kwasu askorbinowego. W związku z tym przybliżenie jest prawidłowe.
pH roztworu wynosi 2,70.
Stężenie dianionu askorbinianu powstającego w drugim etapie reakcji można również obliczyć za pomocą Ka2 i tabeli ICE.
Ka2 jest równe 1,6 × 10−12 i można je wyrazić jako stężenie hydroniu razy stężenie dianionu askorbinianu podzielone przez stężenie monoanionu askorbinianu.
W przypadku tej reakcji tabelę ICE wypełnia się początkowym stężeniem monoanionu askorbinianu i hydroniu z pierwszej reakcji, 0,002 mola. Ze względu na małą wartość x można ją pominąć w stężeniach równowagowych monoanionu askorbinianu i hydroniu.
Po podstawieniu tych wartości w wyrażeniu Ka2 i rozwiązaniu, x wynosi 1,6 ×10−12 zębów trzonowych.
Ponieważ x jest mniejsze niż 5% z 0,002 mola, przybliżenie jest prawidłowe.
Ponieważ stężenie jonów hydroniowych, które powstały podczas drugiego etapu dysocjacji kwasu askorbinowego, jest znikome, pierwszy jonizowalny proton określa pH roztworu.

kwasy poliprotonowe

Kwasy są klasyfikowane według liczby protonów w cząsteczce, które mogą oddać w reakcji. Kwasy takie jak HCl, HNO3 i HCN, które zawierają jeden ulegający jonizacji atom wodoru w każdej cząsteczce, nazywane są kwasami monoprotonowymi. Ich reakcje z wodą to:

<div class="overflow">
<table style="margin-left: auto; margin-right: auto;">
	<tbody>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;">Kwasy monoprotonowe: Reakcje z wodą</td>
		</tr>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;">HCl (aq) + H2O (l) ⟶ H3O+ (aq) + Cl− (aq)</td>
		</tr>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;">HNO3 (aq) + H2O (l) ⟶ H3O+ (aq) + NO3− (aq)</td>
		</tr>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;">HCN (aq) + H2O (l) ⇌ H3O+ (aq) + CN− (aq)</td>
		</tr>
	</tbody>
</table>
</div>

Mimo że zawiera cztery atomy wodoru, kwas octowy CH3CO2H jest również monoprotonowy, ponieważ tylko atom wodoru z grupy karboksylowej (COOH) reaguje z zasadami:

<img alt="Image1" src="/files/ftp_upload/11405/11405_Figure 1.svg" style="height: 125px;" />

Podobnie zasady monoprotyczne to zasady, które akceptują pojedynczy proton.

Kwasy diprotonowe zawierają dwa zdolne do jonizacji atomy wodoru na cząsteczkę; jonizacja takich kwasów zachodzi w dwóch etapach. Pierwsza jonizacja zawsze zachodzi w większym stopniu niż druga jonizacja. Na przykład kwas siarkowy, mocny kwas, jonizuje w następujący sposób:

<div class="overflow">
<table style="margin-left: auto; margin-right: auto;">
	<tbody>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;"></td>
			<td colspan="2" style="color: black; border: 1px solid black; text-align: center;">Kwas diprotowy: Kwas siarkowy (H2SO4)</td>
		</tr>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;">Pierwsza jonizacja</td>
			<td style="color: black; border: 1px solid black; text-align: center;">H2SO4 (aq) + H2O (l) ⇌ H3O+ (aq) + HSO4− (aq)</td>
			<td style="color: black; border: 1px solid black; text-align: center;">Ka1 = more than 102; complete dissociation</td>
		</tr>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;">Druga jonizacja</td>
			<td style="color: black; border: 1px solid black; text-align: center;">HSO4− (aq) + H2O (l) ⇌ H3O+ (aq) + SO42− (aq)</td>
			<td style="color: black; border: 1px solid black; text-align: center;">Ka2 = 1.2 × 10−2</td>
		</tr>
	</tbody>
</table>
</div>

Ten stopniowy proces jonizacji zachodzi dla wszystkich kwasów poliprotonowych. Przykładem słabego kwasu diprotonowego jest kwas węglowy, H2CO3. Pierwsza jonizacja kwasu węglowego daje w małych ilościach jony hydroniowe i jony wodorowęglanowe.

Pierwsza jonizacja: H2CO3 (aq) + H2O (l) ⇌ H3O+ (aq) + HCO3− (aq)

<img alt="Eq1" src="/files/ftp_upload/11405/11405_Equation_1.png" style="height: 90px;" />

Jon wodorowęglanowy może również działać jako kwas. Jonizuje i tworzy jony hydroniowe i jony węglanowe w jeszcze mniejszych ilościach.

Druga jonizacja: HCO3− (aq) + H2O (l) ⇌ H3O+ (aq) + CO32− (aq)

<img alt="Eq2" src="/files/ftp_upload/11405/11405_Equation_2.png" style="height: 90px;" />

KH2CO3 jest większy od KHCO3− 104-krotnie, zatem H2CO3 jest dominującym producentem jonów hydroniowych w roztworze. Oznacza to, że niewielka część HCO3− utworzonego w wyniku jonizacji H2CO3 jonizuje, dając jony hydroniowe (i jony węglanowe), a stężenia H3O+ i HCO3− są praktycznie równe w czystym wodnym roztworze H2CO3.

Jeżeli pierwsza stała jonizacji słabego kwasu diprotonowego jest większa od drugiej co najmniej 20-krotnie, należy potraktować pierwszą jonizację oddzielnie i obliczyć wynikające z niej stężenia przed obliczeniem stężeń związków powstałych w wyniku późniejszej jonizacji. Podejście to zademonstrowano w poniższym przykładowym ćwiczeniu.

Jonizacja kwasu diprotowego

„Woda gazowana” zawiera smaczną ilość rozpuszczonego dwutlenku węgla. Roztwór jest kwaśny, ponieważ CO2 reaguje z wodą, tworząc kwas węglowy, H2CO3. Czym są [H3O+], [HCO3−] i [CO32−] w nasyconym roztworze CO2 o początkowej wartości [H2CO3] = 0,033?

<img alt="Eq3" src="/files/ftp_upload/11405/11405_Equation_3.png" style="height: 90px;" />

Jak wskazują stałe jonizacji, H2CO3 jest znacznie silniejszym kwasem niż HCO3−, zatem etapowe reakcje jonizacji można traktować oddzielnie. Korzystając z dostarczonych informacji, sporządza się tabelę ICE dla tego pierwszego etapu jonizacji:

<div class="overflow">
<table style="margin-left: auto; margin-right: auto;">
	<tbody>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;"></td>
			<td style="color: black; border: 1px solid black; text-align: center;">H2CO3 (wodny) </td>
			<td style="color: black; border: 1px solid black; text-align: center;">H3O+ (wodny)</td>
			<td style="color: black; border: 1px solid black; text-align: center;">HCO3− (wodny)</td>
		</tr>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;">Stężenie początkowe (M)</td>
			<td style="color: black; border: 1px solid black; text-align: center;">0.033</td>
			<td style="color: black; border: 1px solid black; text-align: center;">~0</td>
			<td style="color: black; border: 1px solid black; text-align: center;">0</td>
		</tr>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;">Zmień (M)</td>
			<td style="color: black; border: 1px solid black; text-align: center;">−x</td>
			<td style="color: black; border: 1px solid black; text-align: center;">+x</td>
			<td style="color: black; border: 1px solid black; text-align: center;">+x</td>
		</tr>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;">Stężenie równowagowe (M)</td>
			<td style="color: black; border: 1px solid black; text-align: center;">0.033 − x</td>
			<td style="color: black; border: 1px solid black; text-align: center;">x</td>
			<td style="color: black; border: 1px solid black; text-align: center;">x</td>
		</tr>
	</tbody>
</table>
</div>

Podstawienie stężeń równowagowych do równania równowagi daje

<img alt="Eq4" src="/files/ftp_upload/11405/11405_Equation_4.png" style="height: 90px;" />

Zakładając x << 0,033 i rozwiązując uproszczone równanie, otrzymujemy

<img alt="Eq5" src="/files/ftp_upload/11405/11405_Equation_5.png" style="height: 50px;" />

Tabela ICE zdefiniowała x jako równe molarności jonów wodorowęglanowych i molarności jonów hydroniowych:

<img alt="Eq6" src="/files/ftp_upload/11405/11405_Equation_6.png" style="height: 90px;" />

Wykorzystując obliczone powyżej stężenie jonów wodorowęglanowych, druga jonizacja poddawana jest podobnemu obliczeniu równowagi: HCO3− (aq) + H2O (l) ⇌ H3O+ (aq) + CO32− (aq)

<img alt="Eq7" src="/files/ftp_upload/11405/11405_Equation_7.png" style="height: 180px;" />

Podsumowując: w równowadze [H2CO3] = 0,033 M; [H3O+] = 1,2 × 10-4; [HCO3-] = 1,2 × 10-4 M; i [CO32−] = 4,7 × 10−11 M.

Kwas trójprotonowy to kwas, który ma trzy podatne na jonizację atomy H. Jednym z przykładów jest kwas fosforowy:

<div class="overflow">
<table style="margin-left: auto; margin-right: auto;">
	<tbody>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;"></td>
			<td colspan="2" style="color: black; border: 1px solid black; text-align: center;">Kwas trójprotonowy: Kwas fosforowy (H3PO4)</td>
		</tr>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;">Pierwsza jonizacja</td>
			<td style="color: black; border: 1px solid black; text-align: center;">H3PO4 (aq) + H2O (l) ⇌ H3O+ (aq) + H2PO4− (aq)</td>
			<td style="color: black; border: 1px solid black; text-align: center;">Ka1 = 7,5 × 10−3</td>
		</tr>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;">II jonizacja</td>
			<td style="color: black; border: 1px solid black; text-align: center;">H2PO4− (aq) + H2O (l) ⇌ H3O+ (aq) + HPO42− (aq)</td>
			<td style="color: black; border: 1px solid black; text-align: center;">Ka2 = 6,2 × 10−8</td>
		</tr>
		<tr>
			<td style="color: black; border: 1px solid black; text-align: center;">Trzecia jonizacja</td>
			<td style="color: black; border: 1px solid black; text-align: center;">HPO42− (aq) + H2O (l) ⇌ H3O+ (aq) + PO43− (aq)</td>
			<td style="color: black; border: 1px solid black; text-align: center;">Ka3 = 4,2 × 10−13</td>
		</tr>
	</tbody>
</table>
</div>

Jeśli chodzi o przykłady kwasu diprotonowego, każda kolejna reakcja jonizacji jest mniej rozległa niż poprzednia, co znajduje swoje odzwierciedlenie w malejących wartościach stopniowych stałych jonizacji kwasu. Jest to ogólna cecha kwasów poliprotonowych, a kolejne stałe jonizacji często różnią się od około 105 do 106.

Może się wydawać, że ten zestaw trzech reakcji dysocjacji komplikuje obliczenia stężeń równowagowych w roztworze H3PO4. Jednakże, ponieważ kolejne stałe jonizacji różnią się od 105 do 106 razy, istnieją duże różnice w małych zmianach stężenia towarzyszących reakcjom jonizacji. Pozwala to na stosowanie założeń i procesów upraszczających matematykę, jak pokazano w powyższych przykładach. Zasady poliprotyczne mogą przyjąć więcej niż jeden jon wodorowy. Jon węglanowy jest przykładem zasady diprotycznej, ponieważ może przyjąć dwa protony, jak pokazano poniżej. Podobnie jak w przypadku kwasów poliprotonowych, należy zauważyć, że stałe jonizacji zmniejszają się wraz z etapem jonizacji. Podobnie obliczenia równowagi z udziałem zasad poliprotonowych opierają się na tym samym podejściu, co w przypadku kwasów wieloprotonowych.

<img alt="Eq8" src="/files/ftp_upload/11405/11405_Equation_8.png" style="height: 90px;" />

Kwasy poliprotonowe

Kwasy są klasyfikowane według liczby protonów na cząsteczkę, które mogą oddać w reakcji. Kwasy takie jak HCl, HNO3 i HCN, które zawierają jeden ...

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stepwise ionization of polyprotic acids

Polyprotic acids lose hydrogen ions in steps. The number of ionizable protons in a molecule determines whether an acid is monoprotic, diprotic, or triprotic. This video also shows that polyprotic bases can accept more than one proton.

Monoprotic acids have one ionizable hydrogen atom per molecule. Examples include HCl, HNO3, and HCN. Their reactions with water form hydronium ions and the matching anion. Acetic acid, CH3CO2H, is also monoprotic because only the hydrogen in the carboxyl group reacts with bases. Monoprotic bases accept a single proton.

Diprotic acids have two ionizable hydrogen atoms, so they ionize in two steps. The first ionization is greater than the second. Sulfuric acid is a strong example, with complete first dissociation and a much smaller second dissociation. Carbonic acid, H2CO3, is a weak diprotic acid with the same stepwise pattern. Its first ionization forms hydronium and bicarbonate ions, and its second ionization converts bicarbonate into carbonate in even smaller amounts.

For carbonic acid, the first ionization constant is much larger than the second. In a pure aqueous solution of H2CO3, H3O+ and HCO3− are practically equal, while only a tiny amount of CO3 2− forms. When the first ionization constant is at least 20 times larger than the second, the two steps can be treated separately in equilibrium calculations. The example of saturated CO2 in water uses an ICE table for the first step, then a second equilibrium calculation for bicarbonate.

At equilibrium in that example, [H2CO3] is 0.033 M, [H3O+] is 1.2 × 10−4 M, [HCO3−] is 1.2 × 10−4 M, and [CO3 2−] is 4.7 × 10−11 M. This shows why the first ionization dominates the solution. It also shows how stepwise calculations can simplify polyprotic acid problems.

Triprotic acids have three ionizable hydrogen atoms. Phosphoric acid, H3PO4, is one example. Its three ionization steps produce H2PO4−, then HPO4 2−, and finally PO4 3−. Each successive ionization is less extensive than the one before it. The stepwise acid ionization constants decrease, often by a factor of about 10^5 to 10^6.

That large difference in ionization constants makes equilibrium work easier. Even though a triprotic acid has three dissociation reactions, the small concentration changes can still be handled with simplifying assumptions. Polyprotic bases follow the same idea. The carbonate ion is a diprotic base because it can accept two protons, and its ionization constants also decrease with each step.

Stepwise Ionization of Polyprotic Acids

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polyprotic acids

Polyprotic acids lose hydrogen ions in steps. The number of ionizable protons in a molecule determines whether an acid is monoprotic, diprotic, or triprotic. This video also shows that polyprotic bases can accept more than one proton. Monoprotic acids have one ionizable hydrogen atom per molecule. Examples include HCl, HNO3, and HCN. Their reactions with water form hydronium ions and the matching anion. Acetic acid, CH3CO2H, is also monoprotic because only the hydrogen in the carboxyl group...

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key terms and concepts

Explore how monoprotic, diprotic, and triprotic acids ionize in steps, plus how polyprotic bases accept protons and how to use ICE tables.

Stepwise Ionization of Polyprotic Acids | JoVE K12

chemistry

JoVE Core Chemistry brings general chemistry concepts to life using concise and easy-to-understand animated video lessons. Plus, in the scientist-in-action videos, we demonstrate classical and original research experiments performed in today's laboratories worldwide.

ohios-learning-standards-and-model-curriculum

Ohio’s Learning Standards and Model Curriculum

Interactions Of Matter

Chemical reactions

Minnesota Academic Standards in Science

1.2.1 9L.4.2.2.1

Texas Essential Knowledge and Skills

High School

CHEM.12

CHEM.12.D

Alabama Course of Study Science

Matter and Its Interactions

9-12.PS.3.6.c

Classifying Matter by State

Chemistry is the study of matter and the changes it undergoes. Matter is anything that has mass and occupies space. Matter is all around us; the air, ...

Classifying Matter by Composition

Matter: Pure Substances and Mixtures
According to its composition, the matter can be classified into two broad categories &mdash; pure substances and ...

Elements: Chemical Symbols and Isotopes

A chemical symbol is an abbreviation used to indicate an element or an atom of an element. For example, the symbol for mercury is Hg. The same symbol is ...

Molecules and Compounds

Atoms and Molecules

Everything in the universe is made up of matter, and matter is composed of a combination of elements. An atom is the smallest unit of ...

Solution Formation

There is no one solvent that can dissolve every type of solute. Some substances that readily dissolve in a certain solvent might be insoluble in a ...

Colloids

Children at play often make suspensions such as mixtures of mud and water, flour and water, or a suspension of solid pigments in water known as tempera ...

Construct an explanation to classify matter as a pure substance or mixture; homogeneous or heterogeneous; element or compound; solution, colloid or suspension.

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Phase Transitions

Whether solid, liquid, or gas, a substance&#39;s state depends on the order and arrangement of its particles (atoms, molecules, or ions). Particles in the ...

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Phase Transitions: Vaporization and Condensation

The physical form of a substance changes on changing its temperature. For example, raising the temperature of a liquid causes the liquid to vaporize ...

Vapor Pressure

When a liquid vaporizes in a closed container, gas molecules cannot escape. As these gas phase molecules move randomly about, they will occasionally ...

Clausius-Clapeyron Equation

The equilibrium between a liquid and its vapor depends on the temperature of the system; a rise in temperature causes a corresponding rise in the vapor ...

Phase Transitions: Melting and Freezing

Heating a crystalline solid increases the average energy of its atoms, molecules, or ions, and the solid gets hotter. At some point, the added energy ...

phase-transitions-sublimation-and-deposition

Phase Transitions: Sublimation and Deposition

Some solids can transition directly into the gaseous state, bypassing the liquid state, via a process known as sublimation. At room temperature and ...

Heating and Cooling Curves

When a substance&#8212;isolated from its environment&#8212;is subjected to heat changes, corresponding changes in temperature and phase of the substance ...

Phase Diagrams

A phase diagram combines plots of pressure versus temperature for the liquid-gas, solid-liquid, and solid-gas phase-transition equilibria of a substance. ...

Use models to compare the phases of matter and the physical changes they undergo.

PS.PSc.1.2

physical-and-chemical-properties-of-matter

Physical and Chemical Properties of Matter

The characteristics that enable us to distinguish one substance from another are called properties.

Physical Properties of Matter

A physical property is ...

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Molecular Comparison of Gases, Liquids, and Solids

Particles in a solid are tightly packed together (fixed shape) and often arranged in a regular pattern; in a liquid, they are close together with no ...

Intermolecular vs Intramolecular Forces

Intermolecular forces (IMF) are electrostatic attractions arising from charge-charge interactions between molecules. The strength of the intermolecular ...

Intermolecular Forces

Atoms and molecules interact through bonds (or forces): intramolecular and intermolecular. The forces are electrostatic as they arise from interactions ...

comparing-intermolecular-forces-melting-point-boiling-point

Comparing Intermolecular Forces: Melting Point, Boiling Point, and Miscibility

Intermolecular forces are attractive forces that exist between molecules. They dictate several bulk properties, such as melting points, boiling points, ...

Carry out investigations to compare physical and chemical properties of matter.

PS.PSc.1.3

The Atomic Theory of Matter

The earliest recorded discussion of the basic structure of matter comes from ancient Greek philosophers. Leucippus and Democritus argued that all matter ...

Subatomic Particles

Dalton was only partially correct about the particles that make up matter. All matter is composed of atoms, and atoms are composed of three smaller ...

The Bohr Model

Following the work of Ernest Rutherford and his colleagues in the early twentieth century, the picture of atoms consisting of tiny dense nuclei surrounded ...

Emission Spectra

When solids, liquids, or condensed gases are heated sufficiently, they radiate some of the excess energy as light. Photons produced in this manner have a ...

The de Broglie Wavelength

In the macroscopic world, objects that are large enough to be seen by the naked eye follow the rules of classical physics. A billiard ball moving on a ...

The Uncertainty Principle

Werner Heisenberg considered the limits of how accurately one can measure properties of an electron or other microscopic particles. He determined that ...

Use models to interpret the data presented in Bohr diagrams and electron dot diagrams for neutral atoms of elements 1 through 18.

PS.PSc.1.4

Ions and Ionic Charges

In ordinary chemical reactions, the nucleus &mdash; which contains the protons and neutrons of each atom and thus identifies the element &mdash; remains ...

Use models to compare representations of atoms, ions, and isotopes.

PS.PSc.1.5

The Periodic Table

As early chemists discovered more elements, they realized that various elements could be grouped by their similar chemical behaviors. One such grouping ...

Periodic Classification of the Elements

The periodic table arranges atoms based on increasing atomic number so that elements with the same chemical properties recur periodically. When their ...

atomic-radii-and-effective-nuclear-charge

Atomic Radii and Effective Nuclear Charge

The elements in groups of the periodic table exhibit similar chemical behavior. This similarity occurs because the members of a group have the same number ...

Ionic Radii

Ionic radius is the measure used to describe the size of an ion. A cation always has fewer electrons and the same number of protons as the parent atom; it ...

Ionization Energy

The amount of energy required to remove the most loosely bound electron from a gaseous atom in its ground state is called its first ionization energy ...

Electron Affinity

The electron affinity (EA) is the energy change for adding an electron to a gaseous atom to form an anion (negative ion).



This process can be either ...

Alkali Metals

Group 1 elements are soft and shiny metallic solids. They are malleable, ductile, and good conductors of heat and electricity. The melting points of the ...

Halogens

Group 17 elements, known as halogens, are nonmetals. At room temperature, fluorine and chlorine are gases, bromine is a liquid, and iodine a solid. ...

Noble Gases


The elements in group 18 are noble gases (helium, neon, argon, krypton, xenon, and radon). They earned the name &ldquo;noble&rdquo; because they were ...

Use the Periodic Table as a model to predict the relative properties (metallic/nonmetallic character, ionic charge, and reactivity) and arrangement of elements based on the pattern of valence electrons in the outermost energy levels of atoms.

PS.PSc.1.6

Types of Chemical Bonds

Chemical bonding theories were pioneered by American chemist Gilbert&#xA0;N. Lewis. He developed a model called the Lewis model to explain the type and ...

Ionic Bonding and Electron Transfer

Ions are atoms or molecules bearing an electrical charge. A cation (a positive ion) forms when a neutral atom loses one or more electrons from its valence ...

Covalent Bonding and Lewis Structures

Compared to ionic bonds, which results from the transfer of electrons between metallic and nonmetallic atoms, covalent bonds result from the mutual ...

Bonding in Metals

Metallic bonds are formed between two metal atoms. A simplified model to describe metallic bonding has been developed by Paul Dr&#xFC;de called the ...

Construct an explanation to classify the type of chemical bond that occurs (covalent, ionic, or metallic) in a given substance.

PS.PSc.2.1

Nomenclature of Alkanes

In the late 19th-century, the number of new chemical compounds discovered increased tremendously. Hence, the necessity arose to develop a naming system ...

Nomenclature of Alkenes

The IUPAC naming system for alkenes replaces -an- with -en- in the corresponding parent alkanes. Accordingly, a simple alkene replaces the -ane suffix of ...

Nomenclature of Alkynes

Alkynes are unsaturated hydrocarbons characterized by the presence of carbon-carbon triple bonds and have a general formula CnH2n-2. The nomenclature of ...

structure-and-nomenclature-of-alcohols-and-phenols

Structure and Nomenclature of Alcohols and Phenols

Overview 
Alcohols are one of the most important functional groups in organic chemistry. The name of alcohol comes from the hydrocarbon from which it is ...

Structure and Nomenclature of Ethers

Structure and Bonding
Ethers are organic compounds with an ether functional group which is characterized by an oxygen atom connected to two &#8212; ...

IUPAC Nomenclature of Aldehydes

Aldehydes are named based on the systematic nomenclature rules set by the IUPAC. For acyclic aldehydes, the longest carbon chain containing the aldehydic ...

IUPAC Nomenclature of Ketones

Like aldehydes, ketones are named using IUPAC rules; in this case, by replacing &#8220;e&#8221; in the name of the longest hydrocarbon chain with ...

IUPAC Nomenclature of Carboxylic Acids

IUPAC names of carboxylic acids are systematically derived following a few rules discussed below.
For acyclic saturated monocarboxylic acids, the longest ...

Use models to apply International Union of Pure and Applied Chemistry (IUPAC) conventions to name and write formulas for simple compounds.

PS.PSc.2.2

Understand types, properties, and structure of matter.

Stepwise Ionization of Polyprotic Acids

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