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

K12 Standards

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North Carolina K-12 Science Standard Course of Study

9-12

Physical Science

Matter and its Interactions

PS.PSc.2.5

Polyprotic Acids

フッ化水素酸のような一価酸は、イオン化可能なプロトンを1つ含んでいます。対照的に、ポリプロトン酸には2つ以上のイオン化可能なプロトンが含まれています。例えば、亜硫酸にはイオン化可能なプロトンが2つあり、リン酸には3つのイオン化可能なプロトンがあります。
ポリプロトン酸は、その各プロトンを順次失い、各反応は独自のKaを持っています。
負の電荷がプロトンと陰イオンとの間の結合の強度を増加させるため、負に帯電した分子よりも中性分子からプロトンを除去する方が簡単です。
したがって、リン酸の場合、最初のプロトンであるKa1を除去するためのKAaは、Ka3よりも高い2番目のプロトンであるKa2よりも高くなります。
ポリプロトン酸のpHは、Ka1がその後のKAの1000倍以上大きい場合、最初の反応のみを使用して推定できます。
たとえば、0.050モルのアスコルビン酸溶液のpHは、そのKa1とICEテーブルを使用して決定できます。
アスコルビン酸は、水に溶解すると、ヒドロニウムイオンとアスコルビン酸イオンに解離します。この反応のKa1は8 × 10-5であり、ヒドロニウムの濃度にアスコルビン酸モノアニオンの濃度を掛けたものをアスコルビン酸の濃度で割ったものに等しくなります。
この反応のために、初期濃度と平衡濃度でICEテーブルを調製できます。x の値が小さいため、0.050 から x を引いた値は約 0.050 に等しくなります。
これらの値をKa1の式に代入すると、xの値は0.0020モルに等しくなり、アスコルビン酸の初期濃度のわずか4%になります。したがって、近似は有効です。
溶液のpHは2.70に等しい。
反応の第2ステップで形成されるアスコルビン酸ジアニオンの濃度は、Ka2とICEテーブルを使用して計算することもできます。
Ka2 は 1.6 × 10-12 に等しく、ヒドロニウムの濃度にアスコルビン酸ジアニオンの濃度を掛けたものをアスコルビン酸モノアニオンの濃度で割った値として表すことができます。
この反応では、ICEテーブルに、最初の反応からのアスコルビン酸モノアニオンとヒドロニウムの初期濃度である0.002モルで埋められます。xの値が小さいため、アスコルビン酸モノアニオンとヒドロニウムの平衡濃度から省略できます。
これらの値をKa2式に代入して解くと、xは1.6 ×10-12モルになります。
x は 0.002 モルの 5% 未満であるため、近似は有効です。
アスコルビン酸解離の第2ステップで生成されたヒドロニウムイオンの濃度はごくわずかであるため、第1のイオン化可能なプロトンが溶液のpHを決定します。

多価酸

酸は、反応で与えることのできる1分子あたりのプロトン数によって分類されます。HCl、HNO3、HCNなど、電離可能な水素原子を1分子あたり1つ含む酸を一価の酸と呼びます。これらの酸と水との反応は、
 <table style="margin-left: auto; margin-right: auto;">
 <tbody>
 <tr>
 <td style="color: black; border: 1px solid black; text-align: center;">一価の酸: 水との反応</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>
 酢酸（CH3CO2H）は4つの水素原子を含んでいますが、カルボキシル基（COOH）の水素原子のみが塩基と反応するため、一価の塩基として作用します。
 <img alt="Image1" src="/files/ftp_upload/11405/11405_Figure 1.svg" style="height: 125px;" />
 同様に、一価の塩基は、1つのプロトンを受容する塩基です。
 二価の酸は1分子あたり2つの電離可能な水素原子を含んでおり、電離は2段階で起こります。1段階目の電離の方が2段階目の電離よりも必ず大きくなります。例えば、強酸である硫酸は次のように電離します。
 <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;">二価の酸: 硫酸 (H2SO4)</td>
 </tr>
 <tr>
 <td style="color: black; border: 1px solid black; text-align: center;">1段階目の電離</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;">2段階目の電離</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>
 この段階的な電離プロセスは、すべての多価酸で起こります。炭酸（H2CO3）は、弱い二価酸の一例です。炭酸の1段階目の電離では、少量のヒドロニウムイオンと炭酸水素イオンが生成されます。
 1段階目の電離: H2CO3 (aq) + H2O (l) ⇌ H3O+ (aq) + HCO3− (aq)
 <img alt="Eq1" src="/files/ftp_upload/11405/11405_Equation_1.png" style="height: 90px;" />
 The bicarbonate ion can also act as an acid. It ionizes and forms hydronium ions and carbonate ions in even smaller quantities.
 2段階目の電離: HCO3− (aq) + H2O (l) ⇌ H3O+ (aq) + CO32− (aq)
 <img alt="Eq2" src="/files/ftp_upload/11405/11405_Equation_2.png" style="height: 90px;" />
 KH2CO3はKHCO3−よりも104も大きいので、主にH2CO3が溶液中のヒドロニウムイオンを生成します。つまり、H2CO3がイオン化してできたHCO3はほとんどイオン化せず、ヒドロニウムイオン（および炭酸イオン）を与え、H3O+とHCO3− は、H2CO3の純粋な水溶液中では実質的に等しくなります。
 弱い二価の酸における1段階目の電離定数が2段階目の電離定数よりも少なくとも20倍以上大きい場合、1段階目の電離を別個に扱うのが適切です。その後、得られた濃度を後続の電離に起因する種の濃度計算に用います。この方法を以下の例題で示します。
 二価の酸の電離
 “炭酸水”には、口にすることができる程度の量の二酸化炭素が溶解しています。CO2が水と反応して炭酸（H2CO3）を生成するため、溶液は酸性となります。初期濃度[H2CO3]が0.033であるとき、飽和CO2溶液中における[H3O+]、[HCO3−]、[CO32−]の濃度はそれぞれいくらでしょうか？
 <img alt="Eq3" src="/files/ftp_upload/11405/11405_Equation_3.png" style="height: 90px;" />
 解離定数が示すように、H2CO3はHCO3−よりもはるかに強い酸であるため、段階的な電離反応は個別に扱ってもよいと考えられます。
 <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 (aq) </td>
 <td style="color: black; border: 1px solid black; text-align: center;">H3O+ (aq)</td>
 <td style="color: black; border: 1px solid black; text-align: center;">HCO3− (aq)</td>
 </tr>
 <tr>
 <td style="color: black; border: 1px solid black; text-align: center;">初期濃度 (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;">濃度変化 (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;">平衡濃度 (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>
 この平衡濃度を平衡式に代入すると、
 <img alt="Eq4" src="/files/ftp_upload/11405/11405_Equation_4.png" style="height: 90px;" />
 Assuming x << 0.033 となり、簡略化した式を解くと、
 <img alt="Eq5" src="/files/ftp_upload/11405/11405_Equation_5.png" style="height: 50px;" />
 ICE表では、xは炭酸水素イオンの物質量とヒドロニウムイオンの物質量に等しいと定義されています。
 <img alt="Eq6" src="/files/ftp_upload/11405/11405_Equation_6.png" style="height: 90px;" />
 上記で計算した炭酸水素イオン濃度を用いて、2回目のイオン化も同様の平衡計算を行う: HCO3− (aq) + H2O (l) ⇌ H3O+ (aq) + CO32− (aq)
 <img alt="Eq7" src="/files/ftp_upload/11405/11405_Equation_7.png" style="height: 180px;" />
 まとめ: 平衡において、 [H2CO3] = 0.033 M; [H3O+] = 1.2 × 10−4; [HCO3−] = 1.2 × 10−4 M; and [CO32−] = 4.7 × 10−11 M.
 三価の酸とは、電離可能なH原子を3つ持つ酸のことです。リン酸はその一例です。:
 <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;">三価の酸: リン酸(H3PO4)</td>
 </tr>
 <tr>
 <td style="color: black; border: 1px solid black; text-align: center;">1段階目の電離</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;">2段階目の電離</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;">3段階目の電離</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>
 二価の酸の例のように、連続した電離反応は前段階も小さくなるため、酸解離定数の値は段階とともに減少していきます。これは多価酸の一般的な特徴で、連続する解離定数は約105から106の桁で異なることがよく知られています。
 この3段階の電離反応は、H3PO4の溶液中の平衡濃度の計算を複雑にしているように見えるかもしれません。。しかし、連続する解離定数は、105から106の桁で異なるため、電離反応に伴うわずかな濃度変化にも大きな違いがあます。そのため、上記の例のように、数学的に単純化された仮定やプロセスを用いることができます。多価塩基は2つ以上の水素イオンを受け取ることができます。下図のように、炭酸イオンは2つのプロトンを受け取ることができるため、二価塩基の例となります。多価酸の場合と同様に、解離定数は電離ステップに応じて減少することに注意する必要があます。多価塩基の平衡計算は、多価酸の場合と同様に行うことが出来ます。
 <img alt="Eq8" src="/files/ftp_upload/11405/11405_Equation_8.png" style="height: 90px;" />
 上記の文章は以下から引用した。<a href="https://openstax.org/books/chemistry-2e/pages/14-5-polyprotic-acids"> Openstax, Chemistry 2e, Section 14.5: Polyprotic Acids</a>.

酸は、反応であきらめることができる分子あたりのプロトンの数によって分類されます。HCl、HNO3、HCNなどの酸に含まれるもの...

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KEY TERMS AND CONCEPTS

主要用語と概念

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

bronsted-lowry acids and bases

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relative strengths of conjugate acid-base pairs

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Brønsted-Lowry acid-base chemistry is based on proton transfer. That idea helps show how the strength of an acid is linked to the strength of its conjugate base, and vice versa. Acid and base strength is measured with ionization constants, Ka and Kb, which tell how far an ionization reaction goes. For the conjugate pair HA and A−, the acid ionizes in water and the base reaction can be written for the partner species. When the two reactions are added, they give the autoionization of water. The...

strong acid and base solutions

Strong Acids, Strong Bases, and pH

Strong acids and strong bases change the pH of a solution by dissociating completely in water. A strong acid produces hydronium ions, which are H3O+ ions, and a strong base produces hydroxide ions, OH-. Because the dissociation is complete, the ion concentration can be found from the starting concentration and the molar ratio. For example, 0.20 M hydrobromic acid dissociates fully in water. It produces 0.20 M hydronium ions and 0.20 M bromide ions. A 0.015 M KOH solution also dissociates...

weak acid solutions

Weak Acid Equilibrium in Water

Weak acid equilibrium in water explains why many acids only partially react when dissolved. Most weak acid molecules stay in their original form, and only a small amount of hydronium ions forms. Weak acids are common in nature. They help create the tangy taste of citrus fruits, the stinging sensation from insect bites, and the smells linked to body odor. Acetic acid is a familiar weak acid. It is the main ingredient in vinegar. Its equation uses a double arrow to show that the reaction with...

weak base solutions

Weak Base pH and Kb Calculations

Weak base pH and Kb calculations show how partially reacting bases change water chemistry. Weak bases produce hydroxide ions when they dissolve by reacting with water molecules. Because the reaction only happens partly, these compounds are classified as weak bases. Weak bases are common in nature and in technology. Ammonia is one major example. Global production of ammonia is typically well over 100 metric tons each year. It is used as an agricultural fertilizer, a starting material for...

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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

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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 ...

phase-transitions-vaporization-and-condensation

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 ...

molecular-comparison-of-gases-liquids-and-solids

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.

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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.

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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 ...

nomenclature-of-aromatic-compounds-with-a-single-substituent

Nomenclature of Aromatic Compounds with a Single Substituent

Benzene is the simplest aromatic hydrocarbon or arene. The IUPAC names for simple monosubstituted benzene derivatives are derived by adding the ...

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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