Name: chemical bonding and bond properties
Uploaded: 2020-09-03T13:38:28.000Z
Duration: 2 min 37 s
Channel: JoVE

K12 Standards

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

NC K-12 Science Standard Course of Study

9-12

Chemistry

Matter and its Interactions

PS.Chm.3.1

Types of Chemical Bonds

Kimyasal bağlar, atomların tuz, su veya alaşımlar gibi çeşitli bileşikler oluşturması için gereklidir. Kimyasal bağ oluşumunu veya daha spesifik olarak atomlar arasındaki çekimi anlamak, moleküler davranışı anlamaya ve tahmin etmeye yardımcı olacaktır. Bir atomun çekirdeği, negatif yüklü elektronlarla çevrili nötronlardan ve pozitif yüklü protonlardan oluşur.İki atom birbirine yaklaştığında, bir atomdaki elektronlar diğer atomun çekirdeğine çekilir ve bunun tersi de geçerlidir. Aynı zamanda, her iki atomun çekirdeği, her atomun elektronları gibi birbirini iter. Bu etkileşimler potansiyel enerjide net bir azalmaya yol açtığında, kimyasal bir bağ oluşur.Üç tür kimyasal bağ vardır. Sodyum ve klor gibi bir metal ve ametal iyonik bağ oluşturur. Metaller, elektronların atomdan daha kolay uzaklaştırılmasını sağlayan düşük iyonlaşma enerjisine sahiptir.Bu elektronlar, yüksek elektron ilgileri ve tam bir değerlik kabuğu elde etme eğilimleri nedeniyle ametaller tarafından kolayca kabul edilir. Bu nedenle metal, elektronları bir katyon ve bir anyon oluşturan ametale aktarır. Bu yüklü parçacıklar birbirlerini çekerek iyonik bir bağ oluştururlar.İkinci tip, karbon dioksit oluşturan iki oksijen atomu ve karbon gibi iki ametal arasında oluşan kovalent bağlardır. Ametaller, değerlik elektronlarının bir atomdan diğerine çıkarılmasını ve aktarılmasını zorlaştıran yüksek iyonlaşma enerjisine sahiptir, bu nedenle elektronlar atomlar arasında paylaşılır. Paylaşılan bu elektronlar, bağ atomlarının her iki çekirdeğiyle etkileşime girer ve toplam potansiyel enerjiyi düşürür.Son tür, iki metal atomu arasında oluşan metalik bağdır. Metal atomları valans elektronlarını kolaylıkla kaybederek, en basit elektron denizi modeline göre bir elektron havuzu oluştururlar. Valans elektronları tüm metal üzerinde yer değiştirir ve pozitif yüklü metal atomları, atomları bir arada tutan bu elektron havuzuna çekilir.

kimyasal bağ türleri

Kimyasal bağ teorilerine Amerikalı kimyager Gilbert N. Lewis öncülük etti. Farklı bağların türünü ve oluşumunu açıklamak için Lewis modeli adlı bir model geliştirdi. Kimyasal bağ, kimyanın merkezidir; atomların veya iyonların molekülleri oluşturmak için nasıl birbirine bağlandığını açıklar. Neden bazı bağların güçlü ve diğerlerinin zayıf olduğunu veya neden bir karbonun üç değil de iki oksijenle bağlandığını açıklar; neden su H2O değil H4O'dur. 
 
 <h4>İyonik Bağlar</h4>
 
 İyonlar, elektrik yükü taşıyan atomlar veya moleküllerdir. Bir katyon (bir pozitif iyon), nötr bir atom değerlik kabuğundan bir veya daha fazla elektron kaybettiğinde oluşur ve nötr bir atom, valans kabuğunda bir veya daha fazla elektron kazandığında bir anyon (bir negatif iyon) oluşur. İyonlardan oluşan bileşikler iyonik bileşikler (veya tuzlar) olarak adlandırılır ve bunların kurucu iyonları iyonik bağlarla bir arada tutulur: zıt yüklü katyonlar ve anyonlar arasındaki elektrostatik çekim kuvvetleri.
 
 İyonik bileşiklerin özellikleri, iyonik bağların doğasına biraz ışık tutmaktadır. İyonik katılar kristal bir yapı sergilerler ve sert ve kırılgan olma eğilimindedirler; ayrıca yüksek erime ve kaynama noktalarına sahip olma eğilimindedirler, bu da iyonik bağların çok güçlü olduğunu gösterir. İyonik katılar da aynı nedenden ötürü zayıf elektrik iletkenleridir—iyonik bağların gücü, iyonların katı halde serbestçe hareket etmesini engeller. Bununla birlikte çoğu iyonik katı, suda kolayca çözünür. İyonik bileşikler çözündükten veya eritildikten sonra mükemmel elektrik ve ısı iletkenleridir çünkü iyonlar serbestçe hareket edebilir.
 
 <h4>Kovalent Bağlar</h4>
 
 Ametal atomlar sıklıkla diğer ametal atomlarla kovalent bağlar oluşturur. Kovalent bağlar, elektronlar atomlar arasında paylaşıldığında oluşur ve her iki atomun çekirdeği tarafından çekilir. Kovalent bir bağ oluşturan atomlar, H2, Cl2 ve diğer diatomik moleküllerde olduğu gibi aynı atomlardan oluşuyorsa, bağdaki elektronlar eşit olarak paylaşılmalıdır. Buna saf kovalent bağ denir. Kovalent bir bağla bağlanan atomlar farklı olduğunda, bağ elektronları paylaşılır, ancak artık eşit değildir. Bunun yerine, bağ elektronları bir atoma diğerinden daha fazla çekilir ve bu da elektron yoğunluğunun o atoma doğru kaymasına neden olur. Elektronların bu eşit olmayan dağılımı, polar kovalent bağ olarak bilinir.
 
 Kovalent bağlar içeren bileşikler, iyonik bileşiklerden farklı fiziksel özellikler sergiler. Elektriksel olarak nötr olan moleküller arasındaki çekim, elektrik yüklü iyonlar arasındakinden daha zayıf olduğu için, kovalent bileşikler genellikle iyonik bileşiklerden çok daha düşük erime ve kaynama noktalarına sahiptir. Ayrıca, iyonik bileşikler suda çözündüklerinde iyi elektrik iletkenleri iken, çoğu kovalent bileşik suda çözünmez; elektriksel olarak nötr olduklarından, her durumda zayıf elektrik iletkenleridirler.
 
 <h4>Metalik Bağlar</h4>
 
 İki metal atomu arasında metalik bağlar oluşur. Metalik bağları tanımlamak için basitleştirilmiş bir model Paul Drüde tarafından 'Elektron Denizi Modeli' olarak adlandırılmıştır. Model, metallerin düşük iyonlaşma enerjilerine dayanarak, metal atomlarının değerlik elektronlarını kolaylıkla kaybederek katyonlar haline geldiğini belirtmektedir. Bu değerlik elektronları, tüm metal üzerindeki katyonları çevreleyen bir delokalize elektron havuzu oluşturur. 
 
 Bakır, alüminyum ve demir kristalleri gibi metalik katılar, metal atomlarından oluşur ve hepsi yüksek termal ve elektrik iletkenliği, metalik parlaklık ve işlenebilirlik sergiler. İşlenebilir olmalarından dolayı (basınç veya çekiçleme altında deforme olma yetenekleri) kırılmazlar ve bu nedenle iyi birer inşaat malzemeleri olurlar. Metallerin erime noktaları çok çeşitlidir. Cıva, oda sıcaklığında sıvı haldedir ve alkali metaller 200 °C'nin altında erir. Çeşitli metaller de düşük erime noktalarına sahipken, geçiş metalleri 1000 °C'nin üzerindeki sıcaklıklarda erir. Bu farklılıklar, metaller arasındaki metalik bağın gücündeki farklılıkları yansıtır. 
 
 Bu metin bu kaynaklardan uyarlanmıştır: <a href="https://openstax.org/books/chemistry-2e/pages/7-1-ionic-bonding">Openstax, Chemistry 2e, Section 7.1: Ionic Bonding</a>, <a href="https://openstax.org/books/chemistry-2e/pages/7-2-covalent-bonding">Openstax, Chemistry 2e, Section 7.2: Covalent Bonding</a>, and <big><a href="https://openstax.org/books/chemistry-2e/pages/10-5-the-solid-state-of-matter">Openstax, Chemistry 2e, Section 10.5: The Solid State of Matter</a>.</big>

Kimyasal Bağ Türleri

Kimyasal bağ teorilerine Amerikalı kimyager Gilbert N. Lewis öncülük etti. Türünü açıklamak için Lewis modeli adı verilen bir model geliştirdi ve ...

Education

JoVE Core

Kimya

Chemical Bonding: Basic Concepts

Kimyasal Bağlanma: Temel Kavramlar

KEY TERMS AND CONCEPTS

TEMEL TERİMLER VE KAVRAMLAR

chemical bonding and bond properties

Chemical bonding explains how atoms and ions join to form molecules and compounds. American chemist Gilbert N. Lewis pioneered chemical bonding theory with the Lewis model. This model helps explain why bonds form, why some are stronger than others, and why compounds have fixed formulas like H2O instead of H4O.

Ionic bonding involves ions, which are atoms or molecules with an electrical charge. A cation is a positive ion formed when a neutral atom loses one or more electrons from its valence shell. An anion is a negative ion formed when a neutral atom gains one or more electrons in its valence shell. Ionic compounds, also called salts, are held together by electrostatic attraction between oppositely charged cations and anions.

The properties of ionic compounds show why ionic bonds are strong. Ionic solids usually have a crystalline structure and are rigid and brittle. They also tend to have high melting and boiling points. In the solid state, they are poor conductors of electricity because the ions cannot move freely. Many ionic solids dissolve readily in water. When they are dissolved or melted, they conduct electricity and heat well because the ions can move about freely.

Covalent bonding is common between nonmetal atoms. It forms when atoms share electrons, and the shared electrons are attracted by the nuclei of both atoms. When identical atoms bond, as in H2 and Cl2, the electrons are shared equally. This is called a pure covalent bond. When different atoms bond, the electrons are still shared, but not equally. This creates a polar covalent bond, where electron density shifts toward one atom.

Covalent compounds have different properties from ionic compounds. Because the attraction between neutral molecules is weaker than the attraction between charged ions, covalent compounds usually have much lower melting and boiling points. Most are insoluble in water. They are also poor conductors of electricity in any state because they are electrically neutral.

Metallic bonding forms between metal atoms. Paul Drude's electron sea model describes this bond by saying that metal atoms lose valence electrons easily and become cations. The valence electrons form a pool of delocalized electrons around the cations throughout the metal. Metallic solids, such as copper, aluminum, and iron, conduct heat and electricity well. They also have metallic luster and are malleable, so they can deform under pressure or hammering without shattering.

Metals can have very different melting points. Mercury is liquid at room temperature, and alkali metals melt below 200 degrees Celsius. Several post-transition metals also have low melting points. Transition metals, however, melt above 1000 degrees Celsius. These differences reflect differences in the strength of metallic bonding among metals.

Chemical Bonding and Bond Properties

types of chemical bonds

Chemical bonding explains how atoms and ions join to form molecules and compounds. American chemist Gilbert N. Lewis pioneered chemical bonding theory with the Lewis model. This model helps explain why bonds form, why some are stronger than others, and why compounds have fixed formulas like H2O instead of H4O. Ionic bonding involves ions, which are atoms or molecules with an electrical charge. A cation is a positive ion formed when a neutral atom loses one or more electrons from its valence...

the born-haber cycle

Predicting Ionic Stability with Lattice Energy

Lattice energy helps explain why ionic compounds are stable. It measures the strength of attraction between positive and negative ions in a crystal. In one common definition, lattice energy is the energy required to separate one mole of an ionic solid into gaseous ions, so it has a positive value. Another definition uses the opposite sign and describes the energy released when gaseous ions form a lattice. When checking data, it is important to confirm which convention is being used. In either...

lewis symbols and the octet rule

Valence Electrons, Lewis Symbols, and Bonding

Chemical bonds form when atoms or ions interact in ways that lower the potential energy of a molecule. Gilbert N. Lewis created a simple model to show bond formation using valence electrons, the electrons in the outer shell. In this model, electrons are shared or transferred to help atoms reach a stable electron configuration. The Lewis model helps describe two common bond types. An ionic bond forms when electrons move from a metal to a nonmetal. A covalent bond forms when two nonmetals share...

electronegativity

Electronegativity and Polar Bonds

Electronegativity helps explain why some covalent bonds are nonpolar and others are polar covalent. It is a measure of how strongly an atom attracts shared electrons toward itself. That pull controls how electron density is distributed in a bond. Linus Pauling proposed the first electronegativity values by studying bond energies in heteronuclear molecules such as hydrogen fluoride. He expected the bond energy of HF to be about the average of the bond energies of H2 and F2, or 296 kJ/mol. The...

ionic bonding and electron transfer

Ionic Compounds and Crystal Lattices

Ionic compounds form when positive and negative ions attract each other. A cation is a positive ion, and it forms when an atom loses one or more valence electrons. An anion is a negative ion, and it forms when an atom gains one or more valence electrons. Compounds made of these ions are called ionic compounds, or salts, and the force between them is an ionic bond. The properties of ionic solids help show how strong this attraction is. They usually form rigid, brittle crystals and have high...

trends in lattice energy: ion size and charge

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

Lattice Energy Patterns in Ionic Solids

Lattice energy shows how strongly ions hold an ionic solid together. It is the energy required to separate one mole of a solid into its gaseous ions. For sodium chloride, this process requires 769 kJ per mole. The opposite convention may also be used, where lattice energy is the energy released when gaseous ions form the solid. In either case, a larger magnitude means a more stable ionic compound. For ionic crystals, lattice energy follows a pattern based on charge and ion size. The...

covalent bonding and lewis structures

Shared Electrons in Covalent Molecules

Covalent molecules form when atoms share electrons instead of transferring them. This bonding usually happens between nonmetal atoms with similar tendencies to attract electrons. Because the atoms pull on the electrons in a shared way, the bond is held together by mutual attraction. Covalent compounds often have physical properties that differ from ionic compounds. The attraction between neutral molecules is weaker than the attraction between charged ions. As a result, many covalent compounds...

bond polarity, dipole moment, and percent ionic character

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

How Bond Polarity Shapes Molecular Dipoles

Bond polarity depends on electronegativity, the ability of an atom to attract shared electrons. The absolute value of the electronegativity difference, or ΔEN, gives a rough guide to bond type. When the difference is very small or zero, the bond is covalent and nonpolar. When it is larger, the bond may be polar covalent or ionic. Examples show how this works in real compounds. H–H has a ΔEN of 0, so it is nonpolar. H–Cl has a ΔEN of 0.9, so it is polar covalent. Na–Cl has a ΔEN of 2.1, so it...

lewis structures of molecular compounds and polyatomic ions

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

Drawing Lewis Structures with Valence Electron Counts

Drawing Lewis structures starts with counting valence electrons and building the atom arrangement step by step. Valence electrons are the outer-shell electrons that help show how atoms bond. For ions, a positive charge means one electron is removed for each plus sign, and a negative charge means one electron is added for each minus sign. The next step is to sketch the skeleton structure. The least electronegative atom usually goes in the center, while hydrogen is almost never central. Fluorine...

resonance

Resonance Forms in Lewis Structures

Resonance forms in Lewis structures help explain molecules and ions that cannot be shown correctly with just one drawing. In nitrite ion, NO2−, the Lewis structure can be drawn in two ways. The N-O and N=O bonds switch positions in the two drawings, but the atoms stay in the same arrangement. If nitrite really had one single bond and one double bond, the two bond lengths should be different. A double bond is shorter and stronger than a single bond between the same atoms. Experiments show that...

formal charges

Lewis Structures with Formal Charge

Lewis structures can sometimes show more than one reasonable arrangement for a molecule or polyatomic ion. Formal charge helps chemists choose the best Lewis structure when that happens. It is a useful way to compare possible structures in chemistry. Formal charge is the hypothetical charge an atom would have if bonding electrons were shared evenly between the atoms. It can also be found by starting with the valence electrons of the neutral atom, subtracting the nonbonding electrons, and then...

exceptions to the octet rule

Octet Rule Exceptions in Lewis Structures

Some covalent molecules do not follow the octet rule in their Lewis structures. Their central atoms can fall into three groups: odd-electron molecules, electron-deficient molecules, and hypervalent molecules. These cases show why a Lewis structure may not always give every atom eight valence electrons. Odd-electron molecules have an odd number of valence electrons, so one electron remains unpaired. Molecules with an odd number of electrons are called radicals. Nitric oxide, NO, is one example,...

bond energies and bond lengths

How Bond Energy Predicts Reaction Heat

Bond energy helps explain why molecules stay together and how much heat a reaction may release or absorb. A covalent bond is stronger when more energy is needed to separate the atoms. The energy needed to break one specific covalent bond in one mole of gaseous molecules is called bond energy, or bond dissociation energy. For a diatomic molecule, bond energy is the standard enthalpy change for an endothermic reaction that breaks that bond. The H-H bond is a common example. Its bond energy is...

bonding in metals

Electron Sea Model in Metals

Electron sea model explains how metallic bonding holds metals together. In this model, most metal atoms do not have enough valence electrons to form ionic or covalent bonds in the usual way. Their valence electrons are held loosely because metals have low electronegativity, and their ionization energy is low, so electrons are removed easily. When a metal atom loses these outer electrons, it becomes a positively charged metal ion. The freed electrons form a delocalized electron cloud around...

key terms and concepts

Explore ionic, covalent, and metallic bonding, plus the properties of each. Learn how electrons, ions, and metals explain structure, conductivity, and melting points.

Chemical Bonding and Bond Properties | JoVE K12

chemistry

JoVE Core Kimya, özlü ve kolay anlaşılır animasyon video derslerini kullanarak genel kimya kavramlarına hayat veriyor. Ek olarak, bilim insanı uygulama videolarımız ile klasik ve orijinal araştırma deneylerini dünya çapında günümüz laboratuvarlarında görselleştiriyoruz.

Physical Science

PS.PSc.2.1

ohios-learning-standards-and-model-curriculum

Ohio’s Learning Standards and Model Curriculum

Study Of Matter

Bonding and compounds

Structure And Properties Of Matter

Chemical bonding

Physical Geology

Minerals

Chemical bonding (ionic, covalent, metallic)

Tennessee Academic Standards

High School

Matter and Its Interactions

CHEM1.PS1.14

motion-and-stability-forces-and-interactions

Motion and Stability: Forces and Interactions

CHEM1.PS2.1

CHEM1.PS2.2

Virginia  Standards of Learning

HIgh School

CH.3

CH.3.d

PS.3

PS.3.c

Minnesota Academic Standards in Science

1.2.1 9C.1.2.1.2

Arizona Science Standards

HS.P1

HS.P1U1.2

HS+C.P1

HS+C.P1U1.4

Texas Essential Knowledge and Skills

CHEM.6

CHEM.6.E

Alabama Course of Study Science

9-12.C.2.2.a

9-12.C.2.2.c

Florida Department of Education

SC.912.P.8

SC.912.P.8.6

Chemistry and Physics

IPC.7

IPC.7.A

new-york-state-science-learning-standards

New York State Science Learning Standards

HS. Structure and Properties of Matter

HS-PS1-3.

HS. Chemical Reactions

HS-PS1-2.

HS-PS1-4.

HS-PS1-12.

Georgia Standards of Excellence

SPS2.

Chemical Bonds

SC2.

bonding-types-from-nonpolar-covalent-to-ionic

Bonding Types: From Nonpolar Covalent to Ionic

Scientific Laws and Theories

Scientific Laws

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The Scientific Method

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Classifying Matter by State

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Classifying Matter by Composition

Matter: Pure Substances and Mixtures
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The Atomic Theory of Matter

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Subatomic Particles

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Elements: Chemical Symbols and Isotopes

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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.
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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).



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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

Analyze the structure of atoms and isotopes.

Chemical Bonding and Bond Properties

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