Name: proton transfer in acids and bases
Uploaded: 2020-09-24T15:06:51.000Z
Duration: 2 min 58 s
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Bronsted-Lowry Acids and Bases

חומצת ארניוס היא חומר שמייצר יון מימן כאשר הוא מומס במים, ובסיס ארניוס הוא חומר שמייצר OH או יון הידרוקסיד. חומצת מימן כלורי(הידרוכלורית)היא חומצת ארניוס מכיוון שהיא מתפרקת ליון מימן וליון כלור כשהיא מומסת במים. נתרן הידרוקסיד הוא בסיס ארניוס מפני שהוא מתפרק ליון נתרן וליון הידרוקסיד כשהוא מומס במים.אך לא ניתן להשתמש בהגדרה זו כשמתארים חומצות ובסיסים שאינם מומסים בתמיסה מימית או בסיסים שאינם מכילים יוני הידרוקסיד. הגדרה רחבה יותר לחומצה ניתנה על ידי ברונסטד ולאורי כתורמת של יון מימן או פרוטון, בעוד בסיס הוא מקבל של פרוטון. כשחומצת מימן כלורי מתמוססת במים, היא פועלת כחומצה מפני שהיא תורמת פרוטון למים ליצירית יון הידרוניום ויון כלור.כשאמוניה מתמוססת במים, היא פועלת כבסיס, מקבלת פרוטון מהמים ומייצרת יון אמוניום ויון הידרוקסיד. חומצת ברונסטד לאורי תמיד תגיב עם בסיס ברונסטד לאורי ולהפך. לדוגמה, כשחומצה אצטית תורמת פרוטון, המים פועלים כבסיס ומקבלים את הפרוטון.חומצה אצטית הופכת לבסיס המצומד, אצטט, ומים הופכים לחומצה המצומדת, יון הידרוניום. חומצות ובסיסים שנבדלים זה מזה עקב ההעברה של פרוטון נקראים חומצה-בסיס מצומדים. בתגובה ההפוכה, החומצה המצומדת, הידרוניום, פועלת כתורמת פרוטון, והבסיס המצומד, אצטט, יקבל פרוטון.חוזקה של חומצה נקבע על פי היכולת שלה לתרום פרוטון, בעוד שחוזקו של בסיס נקבע על פי היכולת שלו לקבל פרוטון. לחומצה חזקה יש סבירות גבוהה יותר לתרום פרוטון מאשר לחומצה חלשה יותר. בדומה לכך, לבסיס חזק יש סבירות גבוהה יותר לקבל פרוטון מאשר לבסיס חלש יותר.החוזק של חומצה ושל הבסיס המצומד שלה נמצאים ביחס הפוך. חומצה חזקה מתפרקת לגמרי בתמיסה והבסיס המצומד שנוצר חלש מכדי לקבל פרוטון. דבר דומה תקף במקרה של בסיס חזק והחומצה המצומדת שלו.מצד שני, חומצה חלשה מתפרקת באופן חלקי בתמיסה. הבסיס המצומד של חומצה חלשה גם הוא חלש יחסית. לכן, תערובת של חומצה חלשה לא מפורקת והבסיס הצמוד החלש שלה תימצא במערכת שיווי משקל.תופעה דומה מתרחשת במקרה של בסיס חלש והחומצה המצומדת החלשה שלו.

<ol>
	<li>סיפור, דוד א. "סקירה מהספסל למיטה: היסטוריה קצרה של בסיס חומצה קליני". טיפול נמרץ 8, מס '4 (2004): 253.</li>
</ol>

חומצות ובסיסים של ברונסטד-לאורי

<div style="direction:rtl">


מעמד התגובה חומצה-בסיס נחקר במשך זמן רב. בשנת 1680, רוברט בויל דיווח על תכונות של תמיסות חומצה שכללו את יכולתן להמיס חומרים רבים, לשנות את הצבעים של צבעים טבעיים מסוימים, ולאבד תכונות אלה לאחר שבאו במגע עם תמיסות אלקליות (בסיס). במאה השמונה עשרה, הוכר שלחומצות יש טעם חמוץ, מגיבות עם אבן גיר כדי לשחרר חומר גזי (כיום ידוע כ-CO2), ומקיימות אינטראקציה עם אלקליות ליצירת חומרים ניטרליים. בשנת 1815, האמפרי דייווי תרם רבות לפיתוח תפיסת החומצה-בסיס המודרנית בכך שהדגים כי מימן הוא המרכיב החיוני של חומצות. בערך באותו זמן, ז'וזף לואי גה-לוסאק הגיע למסקנה שחומצות הן חומרים שיכולים לנטרל בסיסים ושניתן להגדיר את שני סוגי החומרים הללו רק במונחים של זה. משמעות המימן הודגשה מחדש בשנת 1884 כאשר סוונטה ארניוס הגדיר חומצה כתרכובת שמתמוססת במים כדי לייצר קטיוני מימן (המוכרים כעת כיוני הידרוניום) ובסיס כתרכובת שמתמוססת במים כדי להניב אניונים הידרוקסידים. 


חומצות ובסיסים של ברונסטד-לאורי 

יוהנס ברונסטד ותומס לאורי הציעו תיאור כללי יותר בשנת 1923 שבו חומצות ובסיסים הוגדרו במונחים של העברת יוני מימן, H+. (שימו לב שלעתים קרובות מתייחסים ליוני מימן אלה פשוט כפרוטונים, מכיוון שאותו חלקיק תת-אטומי הוא המרכיב היחיד של קטיונים שמקורם באיזוטופ המימן הנפוץ ביותר, 1H.) תרכובת שתורמת פרוטון לתרכובת אחרת נקראת חומצה ברונסטד-לאורי , ותרכובת שמקבלת פרוטון נקראת בסיס ברונסטד-לאורי. תגובת חומצה-בסיס היא, אם כן, העברה של פרוטון מתורם (חומצה) למקבל (בסיס). 

הרעיון של זוגות מצומדים שימושי בתיאור תגובות חומצה-בסיס של ברונסטד-לאורי (וגם תגובות הפוכות אחרות). כאשר חומצה תורמת H+, המין שנותר נקרא הבסיס המצומד של החומצה מכיוון שהוא מגיב כמקבל פרוטונים בתגובה ההפוכה. באופן דומה, כאשר בסיס מקבל H+, הוא הופך לחומצה המצומדת שלו. התגובה בין מים ואמוניה ממחישה רעיון זה כפי שמוצג להלן. 
<img alt="Eq1" src="/files/ftp_upload/11394/11394_Equation_1.png" style="height: 50px;"> 

בכיוון קדימה, מים פועלים כחומצה על ידי תרומת פרוטון לאמוניה ובהמשך הופכים ליון הידרוקסיד, OH− הבסיס המצומד של המים. האמוניה פועלת כבסיס בקבלת פרוטון זה, והופכת ליון אמוניום, NH4+, החומצה המצומדת של אמוניה. בכיוון ההפוך, יון הידרוקסיד פועל כבסיס בקבלת פרוטון מיון אמוניום, הפועל כחומצה. 

חומצות ובסיסים חזקים מתנתקים לחלוטין בתמיסה. החומצות והבסיסים המצומדים שלהם חלשים ביותר ואינם יכולים לתרום או לקבל את הפרוטונים, בהתאמה, כדי לבצע את התגובה ההפוכה; לכן, תגובות המערבות חומצות ובסיסים חזקות מסתיימות למעשה כשהן בתמיסה מימית. מצד שני, חומצות ובסיסים חלשים מתפרקים חלקית בתמיסות ומייצרים בסיסים וחומצות מצומדים חלשים, בהתאמה. חומצות או בסיסים מצומדים חלשים אלו יכולים לבצע את התגובה ההפוכה, וכך תגובות של חומצה חלשה ובסיס מגיעות לשיווי משקל בהתאם לחוזקות היחסיות של החומצות והבסיסים החלשים. לסיכום, חומצה חזקה יותר תייצר את הבסיס המצומד החלש באותה מידה ואילו בסיס חזק יותר ייצור את החומצה המצומדת החלשה באותה מידה ולהיפך. טבלה 1 מתארת את הקשר בין זוגות חומצה-בסיס מצומדים שונים. 

<table style="margin-left: auto; margin-right: auto;">
<tbody>
<tr>
<td style="color: black; border: 1px solid black; text-align: center;">חומצה חזקה</td>
<td style="color: black; border: 1px solid black; text-align: center;"> בסיס מצומד חלש מאוד</td>
</tr>
<tr>
<td style="color: black; border: 1px solid black; text-align: center;">HCl</td>
<td style="color: black; border: 1px solid black; text-align: center;">Cl−</td>
</tr>
<tr>
<td style="color: black; border: 1px solid black; text-align: center;">HNO3</td>
<td style="color: black; border: 1px solid black; text-align: center;">NO3−</td>
</tr>
<tr>
<td colspan="2"></td>
</tr>
<tr>
<td style="color: black; border: 1px solid black; text-align: center;">חומצה חלשה</td>
<td style="color: black; border: 1px solid black; text-align: center;">בסיס מצומד חלש</td>
</tr>
<tr>
<td style="color: black; border: 1px solid black; text-align: center;">HF</td>
<td style="color: black; border: 1px solid black; text-align: center;">F−</td>
</tr>
<tr>
<td style="color: black; border: 1px solid black; text-align: center;">NH4+</td>
<td style="color: black; border: 1px solid black; text-align: center;">NH3</td>
</tr>
<tr>
<td colspan="2"></td>
</tr>
<tr>
<td style="color: black; border: 1px solid black; text-align: center;">חומצה חלשה מאוד</td>
<td style="color: black; border: 1px solid black; text-align: center;">בסיס מצומד חזק</td>
</tr>
<tr>
<td style="color: black; border: 1px solid black; text-align: center;">OH−</td>
<td style="color: black; border: 1px solid black; text-align: center;">O2−</td>
</tr>
<tr>
<td style="color: black; border: 1px solid black; text-align: center;">CH4</td>
<td style="color: black; border: 1px solid black; text-align: center;">CH3−</td>
</tr>
</tbody>
</table>

טבלה 1: חוזק יחסי של כמה זוגות חומצה-בסיס מצומדים. 

טקסט זה מותאם מ<a href="https://openstax.org/books/chemistry-2e/pages/14-1-bronsted-lowry-acids-and-bases">Openstax, Chemistry 2e, Section 14.4 Brønsted-Lowry Acid and Bases</a>.</div>

שיעור התגובה החומצית-בסיסית נחקר מזה זמן רב. בשנת 1680 דיווח רוברט בויל על תכונות של תמיסות חומצה שכללו את יכולתן ...

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מונחים ומושגים מרכזיים

proton transfer in acids and bases

Acids and bases can be understood through proton transfer. Early scientists described acids by their sour taste, their effect on dyes, and their reaction with limestone, which releases carbon dioxide. Robert Boyle also noted that acid solutions can lose these properties after contact with alkali, or base, solutions.

The modern view developed step by step. Humphry Davy showed that hydrogen is the essential part of acids. Joseph Louis Gay-Lussac then described acids as substances that neutralize bases. In 1884, Svante Arrhenius defined acids as compounds that produce hydrogen cations in water and bases as compounds that produce hydroxide anions.

Brønsted and Lowry gave a broader definition in 1923. A Brønsted-Lowry acid donates a proton, and a Brønsted-Lowry base accepts a proton. An acid-base reaction is the transfer of that proton from the donor to the acceptor. The hydrogen ion, H+, is often called a proton because it is the only particle in the most common hydrogen isotope.

Conjugate pairs help describe these reactions. After an acid donates H+, the species left behind is its conjugate base. After a base accepts H+, it becomes its conjugate acid. Water and ammonia show this clearly. In the forward direction, water donates a proton to ammonia, so water acts as an acid and becomes hydroxide, OH−, while ammonia acts as a base and becomes ammonium, NH4+.

The reverse reaction also fits the same pattern. Hydroxide can accept a proton, so it acts as a base. Ammonium can donate a proton, so it acts as an acid. Strong acids and strong bases dissociate completely in solution, and their conjugate acids and bases are extremely weak. That is why reactions with strong acids and bases in water usually go to completion.

Weak acids and weak bases behave differently. They only partially dissociate in solution and form weak conjugate bases or weak conjugate acids. These conjugate species can take part in the reverse reaction, so weak acid-base reactions reach equilibrium. In general, a stronger acid gives a weaker conjugate base, and a stronger base gives a weaker conjugate acid.

Proton Transfer in Acids and Bases

bronsted-lowry acids and bases

Acids and bases can be understood through proton transfer. Early scientists described acids by their sour taste, their effect on dyes, and their reaction with limestone, which releases carbon dioxide. Robert Boyle also noted that acid solutions can lose these properties after contact with alkali, or base, solutions. The modern view developed step by step. Humphry Davy showed that hydrogen is the essential part of acids. Joseph Louis Gay-Lussac then described acids as substances that neutralize...

water: a bronsted-lowry acid and base

Water as an Amphiprotic Substance

Water can act as both a Brønsted-Lowry acid and a Brønsted-Lowry base. When hydrogen fluoride dissolves in water, it donates protons to water. This is acid ionization. The products are hydronium ions and fluoride ions. Water can also accept protons from another substance. When pyridine dissolves in water, it accepts a proton from water molecules. This is base ionization. The products are hydroxide ions and pyridinium ions. These reactions show that water can play either role. A substance that...

ph scale

pH and pOH in Water

pH and pOH show how hydronium and hydroxide ions behave in water and other aqueous solutions. These ion concentrations are linked by the ion product of water, K w , so when one goes up, the other goes down. Because ion concentrations can differ by huge amounts, a logarithmic scale is used to describe them. pH is defined from the hydronium ion concentration, [H3O+], and pOH is the matching p-function for hydroxide ion concentration. These two values are also connected through the K w...

relative strengths of conjugate acid-base pairs

relative-strengths-of-conjugate-acid-base-pairs

How Ka and Kb Show Acid-Base Strength

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...

mixtures of acids

pH of Acid Mixtures

The pH of acid mixtures depends on the acids present, their dissociation constants, and their starting concentrations. When a solution contains two different acids, the pH can be found by choosing the method that fits their relative strengths. This makes acid mixtures a useful case for applying acid-base rules in chemistry. In a mixture of a strong acid and a weak acid, the strong acid dissociates completely and supplies almost all of the hydronium ions in the solution. The weak acid...

ions as acids and bases

Salt Hydrolysis and pH of Solutions

Salt hydrolysis explains why some salt solutions are acidic, basic, or neutral. Salts are ionic compounds made of cations and anions. In water, either ion may react with water through an acid or base ionization reaction. The pH of the solution depends on the relative acid-base strength of the ions in the salt. Ammonium chloride is a good example of an acidic salt. When it dissolves, it separates into ammonium ions and chloride ions. The ammonium ion is the conjugate acid of ammonia, so it can...

determining the ph of salt solutions

Salt Hydrolysis and pH in Solutions

Salt hydrolysis and pH in solutions depend on the ions released when a salt dissolves. Some ions react with water, while others do not. The balance between the cation and anion helps show whether the solution becomes acidic, basic, or neutral. Salts with pH-neutral anions and cations that produce hydronium ions give acidic solutions with pH below 7. Ammonium nitrate is one example. In NH4NO3, NO3− does not react with water, but NH4+ forms hydronium ions, so the solution is acidic. Other salts...

acid/base strengths and dissociation constants

acidbase-strengths-and-dissociation-constants

Acid and Base Strength in Water

Acid and base strength in water depends on how much a substance ionizes after it dissolves. If ionization is nearly complete, the substance is called strong. If only a small amount ionizes, it is called weak. Weak acids and weak bases are much more common than strong ones. The most common strong acids are HClO4, HCl, HBr, HI, HNO3, and H2SO4. The most common strong bases are LiOH, NaOH, KOH, Ca(OH)2, Sr(OH)2, and Ba(OH)2. These strong acids and bases ionize essentially completely in water. <br...

polyprotic acids

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...

acid strength and molecular structure

How Bonding Affects Acid Strength

Acid strength depends on bonding, electronegativity, and oxidation number. These factors help explain why some hydrogen compounds act as strong acids, while others behave as weak acids or bases. For binary acids, which are hydrogen compounds with one other nonmetal, acidity increases as the H-A bond gets weaker down a group. That is why the order for group 17 is HF &lt; HCl &lt; HBr &lt; HI, and for group 16 it is H2O &lt; H2S &lt; H2Se &lt; H2Te. Across a period, acid strength increases as...

lewis acids and bases

Electron-Pair Reactions in Acid-Base Chemistry

Electron-pair reactions explain Lewis acid-base chemistry. In 1923, G. N. Lewis described acids and bases by how they accept or donate a pair of electrons. When that electron pair forms a coordinate covalent bond, one atom supplies both bonding electrons. This bond is also called a dative bond. A simple example is the reaction of water with a hydrogen ion to make a hydronium ion. Ammonia can also combine with a hydrogen ion to form an ammonium ion. In both cases, the reaction creates a Lewis...

key terms and concepts

Learn how Brønsted-Lowry acids and bases work through proton transfer, conjugate pairs, and the difference between strong and weak acid-base reactions.

Proton Transfer in Acids and Bases | JoVE K12

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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 ...

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 ...

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 ...

Use models to explain how the scientific understanding of atomic structure has evolved.

PS.Chm.1.1

Radioactivity and Nuclear Equations

Nuclear chemistry is the study of reactions that involve changes in nuclear structure. The nucleus of an atom is composed of protons and, except for ...

Types of Radioactivity

The most common types of radioactivity are &#945; decay, &#946; decay, &#947; decay, neutron emission, and electron capture.
Alpha (&#945;) decay is the ...

Nuclear Stability

Protons and neutrons, collectively called nucleons, are packed together tightly in a nucleus. With a radius of about 10&#8722;15 meters, a nucleus is ...

Nuclear Binding Energy

The difference between the calculated and experimentally measured masses is known as the mass defect of the atom. In the case of helium-4, the mass defect ...

Radioactive Decay and Radiometric Dating

Radioactivity is a spontaneous disintegration of an unstable nuclide and is a random process, as all the nuclei in the sample do not decay simultaneously. ...

Nuclear Fission

Many heavier elements with smaller binding energies per nucleon can decompose into more stable elements that have intermediate mass numbers and larger ...

Nuclear Power

Controlled nuclear fission reactions are used to generate electricity. Any nuclear reactor that produces power via the fission of uranium or plutonium by ...

Nuclear Fusion

The process of converting very light nuclei into heavier nuclei is also accompanied by the conversion of mass into large amounts of energy, a process ...

Nuclear Transmutation

Nuclear transmutation is the conversion of one nuclide into another. It can occur by the radioactive decay of a nucleus, or the reaction of a nucleus with ...

Use models to compare nuclear reactions including alpha decay, beta decay and gamma decay; nuclear fusion and nuclear fission.

PS.Chm.1.2

Atomic Orbitals

An atomic orbital represents the three-dimensional regions in an atom where an electron has the highest probability to reside. The radial distribution ...

The Pauli Exclusion Principle

The arrangement of electrons in the orbitals of an atom is called its electron configuration. We describe an electron configuration with a symbol that ...

The Energies of Atomic Orbitals

In an atom, the negatively charged electrons are attracted to the positively charged nucleus. In a multielectron atom, electron-electron repulsions are ...

The Aufbau Principle and Hund's Rule

To determine the electron configuration for any particular atom, we can build the structures in the order of atomic numbers. Beginning with hydrogen, and ...

electron-configuration-of-multielectron-atoms

Electron Configuration of Multielectron Atoms

The alkali metal sodium (atomic number 11) has one more electron than the neon atom. This electron must go into the lowest-energy subshell available, the ...

Use models to explain how electrons are distributed in atoms.

PS.Chm.1.3

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 ...

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 ...

Atomic Mass

Atoms &mdash; and the protons, neutrons, and electrons that compose them &mdash; are extremely small. For example, a carbon atom weighs less than 2 ...

Molar Mass

The identity of a substance is defined not only by the types of atoms or ions it contains but by the quantity of each type of atom or ion. For example, ...

Use the Periodic Table as a model to predict the relative properties of elements based on the pattern of valence electrons in the outermost energy levels of atoms.

PS.Chm.2.1

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 ...

Construct an explanation to infer the atomic size, reactivity, electronegativity, and ionization energy of an element based on its position in the Periodic Table.

PS.Chm.2.2

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 ...

Lewis Symbols and the Octet Rule

Chemical bonds are complex interactions between two or more atoms or ions, which reduce the potential energy of the molecule. Gilbert N. Lewis developed a ...

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 ...

The Born-Haber Cycle

Lattice Energy&#xA0;

An ionic compound is stable because of the electrostatic attraction between its positive and negative ions. The lattice energy of a ...

trends-in-lattice-energy-ion-size-and-charge

Trends in Lattice Energy: Ion Size and Charge

An ionic compound is stable because of the electrostatic attraction between its positive and negative ions. The lattice energy of a compound is a measure ...

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 ...

Electronegativity

Whether a bond is nonpolar or polar covalent is determined by a property of the bonding atoms called electronegativity.&#xA0;

Electronegativity values of ...

bond-polarity-dipole-moment-and-percent-ionic-character

Bond Polarity, Dipole Moment, and Percent Ionic Character

Bond Polarity

The absolute value of the difference in electronegativity (&Delta;EN) of two bonded atoms provides a rough measure of the polarity to be ...

lewis-structures-of-molecular-compounds-and-polyatomic-ions

Lewis Structures of Molecular Compounds and Polyatomic Ions

To draw Lewis structures for complicated molecules and molecular ions, it is helpful to follow a step-by-step procedure as outlined:


	Determine the ...

Resonance

The Lewis structure of a nitrite anion (NO2&minus;) may actually be drawn in two different ways, distinguished by the locations of the N-O and N=O ...

Formal Charges

In some cases, there are seemingly more than one valid Lewis structures for molecules and polyatomic ions. The concept of formal charges can be used to ...

Exceptions to the Octet Rule

Many covalent molecules have central atoms that do not have eight electrons in their Lewis structures. These molecules fall into three categories:


	...

Bond Energies and Bond Lengths

Stable molecules exist because covalent bonds hold the atoms together. The strength of a covalent bond is measured by the energy required to break it, ...

Analyze and interpret data to explain the mechanisms and properties of the two main types of intramolecular (ionic and covalent) bonds.

PS.Chm.3.1

Analyze the structure of atoms and isotopes.

Proton Transfer in Acids and Bases

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