Name: atomic orbitals and quantum numbers
Uploaded: 2023-04-30T18:28:31.000Z
Duration: 2 min 28 s
Channel: JoVE

K12 Standards

Louisiana Student Standards for Science

High School

Chemistry

Matter And Its Interactions

HS-PS1-1

Electronic Structure of Atoms

원자는 전자, 양성자 및 중성자라는 세 가지 아원자 입자로 만들어집니다. 양전하 양성자와 전기중립중성자는 원자핵을 구성하며, 여기서 모든 양성 전하와 원자질량의 대부분이 상주한다.
전자는 핵 주위의 빈 공간에 있는 음전하, 저질량 성분입니다. 원자는 양성자만큼 많은 전자를 가지고 있을 때 전기적으로 중립적입니다.
전자는 입자와 파도와 같은 이중 특성을 나타낸다. 공간에서의 위치와 에너지는 보완적인 특성입니다. 따라서, 잘 정의 된 에너지를 가진 전자의 경우, 그 위치는 불확실하다.
원자의 양자 기계 모델은 공간에서 3차원 영역에서 주어진 에너지의 전자를 찾을 확률이 전자의 파도 같은 특성을 표현하는 파장의 제곱으로부터 결정될 수 있다고 예측하며, 이는 전자 확률 밀도라고도 한다.
원자에서 특정 에너지의 전자의 가능한 공간 위치를 설명하는 함수를 원자 궤도라고합니다.
각 궤도는 세 개의 양자 숫자의 고유한 조합에 해당합니다. 주요 양자 번호, n,에너지 레벨 또는 쉘로 궤도를 그룹.
각 운동량 또는 아지무탈, 양자 번호, l,쉘 내의 궤도를 하위 쉘로 그룹화합니다. l의 각 값은 다양한 형상의 s, p, d또는 f 궤도에 해당합니다.
일부 궤도 모양은 각각 자기 양자 번호, ml과관련된 여러 가능한 방향을 가질 수 있다. 지정된 하위 셸의 방향 수는2l+ 1과 같습니다.
네 번째 양자 번호 -스핀 양자 번호, ms-궤도를 점유 하는 전자와 연결 하 고 두 개의 가능한 값: '플러스 절반 절반' 그리고 '마이너스 절반'. 이렇게 하면 원자에 있는 두 개의 전자가 네 개의 양자 숫자에 대해 동일한 값을 갖지 않습니다.
궤도를 서로 겹겹살으로 덮어 놓는 것은 핵을 둘러싼 전자의 '구름'과 같은 대략 구형 모양을 생성합니다. 원자가 일반적으로 구체로 표시되는 이유입니다.

원자의 전자 구조

원자는 중앙 핵 내부에 포함된 양성자와 중성자로 구성되며이는 핵이라고 불리는 단단한 입자로 이루어져 있으며, 핵 주위에는 전자가 존재합니다. 양자역학은 전자의 파동-입자 이중성과 핵 주변 위치의 불확실성을 고려하여 원자 구조에 대한 보다 정확한 모델을 제공합니다. 이는 원자 궤도를 이산 에너지의 전자가 존재하는 핵 주변 영역으로 설명하며 n, l, m_l 및 m_s의 네 가지 양자수를 특징으로 합니다.

양자 역학 모델

원자는 전자로 둘러싸인 작은 양전하 핵으로 구성됩니다. 핵에는 양성자와 중성자가 포함되어 있습니다. 양성자의 전하량은 +1이고 질량은 1.0073 amu입니다. 중성자는 전하가 0이고 질량이 1.0087amu입니다. 전자의 전하량은 -1이고 질량은 0.00055 amu입니다. 핵에 있는 양성자의 수를 원자 번호(Z)라고 하며 원자의 원소 정체성을 정의합니다. 핵에 있는 양성자와 중성자 수의 합을 질량수라고 하며 amu로 표시되며 원자의 질량과 거의 같습니다. 원자는 동일한 수의 전자와 양성자를 포함할 때 중성입니다.

핵 주변의 전자 분포를 설명하는 원자 구조를 설명하기 위해 다양한 모델이 제안되었습니다. 드브로이 관계식은 전자가 입자와 파동의 성질을 모두 갖고 있음을 정량화한 것입니다. 이 파동-입자 이중성을 더욱 정량화하여 하이젠베르크는 불확정성 원리를 제시했습니다. 즉 전자의 위치(입자 특성과 관련됨)와 속도 또는 에너지(파동 특성과 관련됨)는 완전한 정밀도로 동시에 결정될 수 없다는 것입니다. 양자역학적 모델은 원자 구조에 대한 보다 정확한 그림을 제공합니다. 이는 원자에 포함된 특정 에너지를 갖는 전자의 3차원 위치를 파동함수 ψ^2의 제곱을 통해 확률적으로 설명합니다. 원자 파동함수 또는 원자 궤도는 전자가 발견될 가능성이 가장 높은 원자의 영역을 설명합니다.

원자 오비탈은 세 개의 양자수로 결정됩니다. 주요 양자수 n은 에너지 준위 또는 '껍질'의 위치 측면에서 오비탈을 그룹화합니다. 각운동량 또는 방위각 양자수 l은 모양에 따라 궤도를 '하위 껍질'로 그룹화합니다. 0에서 n – 1 사이의 정수 값을 가지며 문자로 표시됩니다: s(l = 0), p(l = 1), d(l = 2), f(l = 3), g(l = 4) , 및 h(l = 5). –l에서 +l 사이의 2l + 1 값을 갖는 자기 양자수 m_l는 공간에서 오비탈의 방향을 나타냅니다. 또한 각 전자는 ±1/2에 해당하는 스핀 양자수 m_s를 갖습니다. 동일한 원자에 있는 두 개의 전자는 네 개의 양자수 모두에 대해 동일한 값 세트를 가질 수 없습니다.

이 문서는 에서 발췌되었습니다<a href="https://openstax.org/books/chemistry-2e/pages/6-3-development-of-quantum-theory#0"> Openstax, Chemistry 2e, Section 6</a>.


원자는 양성자와 중성자로 구성되며, 핵이라고 하는 조밀한 중심 핵 내부에 포함되어 있으며 주변에 전자가 존재합니다.

Education

교육

JoVE Core

Organic Chemistry

유기 화학

Unit 1

제1단원

Covalent Bonding and Structure

공유 결합과 구조

KEY TERMS AND CONCEPTS

주요 용어 및 개념

atomic orbitals and quantum numbers

Atomic orbitals and quantum numbers describe how electrons are arranged around the nucleus. An atom has a small, positively charged nucleus with electrons surrounding it. The nucleus contains protons and neutrons, and the quantum mechanical model gives a better picture of this structure than older models.

Protons carry a +1 charge and have a mass of 1.0073 amu. Neutrons have no charge and have a mass of 1.0087 amu. Electrons carry a −1 charge and have a mass of 0.00055 amu. The number of protons is the atomic number, Z, and it defines the element. The total number of protons and neutrons is the mass number, and it is approximately equal to the atom’s mass in amu. An atom is neutral when it has equal numbers of protons and electrons.

The quantum model grew from ideas about electron behavior. The de Broglie relation showed that electrons act like both particles and waves. Heisenberg’s uncertainty principle added that an electron’s position and its velocity or energy cannot both be known with full precision at the same time. Because of this, electron location is described in a probabilistic way using the square of the wavefunction, ψ².

Atomic wavefunctions, or atomic orbitals, show the regions where electrons are most likely to be found. Orbitals are described by four quantum numbers. The principal quantum number, n, gives the energy level or shell. The angular momentum, or azimuthal, quantum number, l, describes orbital shape and forms subshells. Its values run from 0 to n − 1, and the labels are s, p, d, f, g, and h for l = 0 through 5.

The magnetic quantum number, ml, describes how an orbital is oriented in space. It has 2l + 1 possible values, ranging from −l to +l. The spin quantum number, ms, can be +1/2 or −1/2. No two electrons in the same atom can have the same set of values for all four quantum numbers.

Atomic Orbitals and Quantum Numbers

what is organic chemistry?

Carbon Compounds in Everyday Life

Organic chemistry focuses on carbon compounds called organic compounds. These compounds may come from living things or be made by chemists. Carbon is the main element in them, and it bonds with other carbon atoms as well as hydrogen, oxygen, nitrogen, and sulfur. Carbon can form up to four strong bonds. That ability lets carbon atoms build chains and rings of many sizes, shapes, and levels of complexity. Not every carbon-containing substance is classified as organic. Carbonates, cyanides, and...

electronic structure of atoms

Atomic orbitals and quantum numbers describe how electrons are arranged around the nucleus. An atom has a small, positively charged nucleus with electrons surrounding it. The nucleus contains protons and neutrons, and the quantum mechanical model gives a better picture of this structure than older models. Protons carry a +1 charge and have a mass of 1.0073 amu. Neutrons have no charge and have a mass of 1.0087 amu. Electrons carry a −1 charge and have a mass of 0.00055 amu. The number of...

electron configurations

How Electrons Fill Atomic Orbitals

Electron filling in atoms follows a set order based on orbital energy. The Aufbau principle says each new electron enters the lowest-energy subshell available. The Pauli exclusion principle says no two electrons can share the same set of four quantum numbers. Hund’s rule of maximum multiplicity says electrons stay unpaired in equal-energy orbitals when possible. The order of filling follows the relative energies of the subshells. A common sequence is 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, and so on.

chemical bonds

Chemical Bonds: Types and Strength

Chemical bonds help atoms reach a full valence shell like the nearest noble gas. The main bond types are ionic, covalent, and metallic. Bond energy and bond length also help explain how strong a bond is. An ionic bond forms from electrostatic attraction between cations and anions. In many cases, one atom transfers electrons to another atom, and the ions form from that transfer. Ionic bonds have no defined direction because the attraction spreads evenly through three-dimensional space. A...

polar covalent bonds

Electronegativity in Polar Covalent Bonds

Polar covalent bonds form when atoms share electrons unevenly. This happens in covalent bonds between atoms that have similar, but not identical, tendencies to attract electrons. Nonmetal atoms often make these bonds with other nonmetals. Hydrogen gas, H2, is a simple example of a covalent bond between two hydrogen atoms. A covalent bond begins when two atoms move close enough for their valence orbitals to overlap. In hydrogen, the 1s orbitals overlap and the single electrons on each atom...

lewis structures and formal charges

Lewis Structures, Bonds, and Formal Charge

Lewis structures show how atoms share electrons in covalent bonds and in polyatomic ions. Lewis symbols help draw these structures, and the periodic table helps predict how many valence electrons an atom has and how many bonds it can form to reach an octet. Group 18 elements, such as argon and helium, already have filled electron configurations. They rarely take part in chemical bonding. Atoms in group 17, such as bromine and iodine, need one more electron to reach an octet, so they can form...

vsepr theory

Molecular Shapes from Electron Pairs

Molecular shape can be predicted from the way electron pairs arrange around a central atom. Valence shell electron-pair repulsion theory, or VSEPR theory, uses a Lewis structure to count bonding pairs and lone electron pairs. The main idea is simple: electron pairs spread out as far as possible to reduce repulsion. In a molecule, the valence electrons around the central atom can be bonding pairs or lone pairs. Bonding pairs are found mainly between bonded atoms. Lone pairs stay on one atom and...

molecular geometry and dipole moments

Predicting Shape and Molecular Polarity

Molecular shape and molecular polarity can be predicted with VSEPR theory and dipole moments. Start by writing the Lewis structure of the molecule or polyatomic ion. Then count the electron groups around the central atom. Lone pairs and bonds both count as electron groups, and a single, double, or triple bond each counts as one region of electron density. Use that count to identify the electron-pair geometry. Next, use the number of lone pairs to determine the molecular structure. If more than...

resonance and hybrid structures

Resonance in Nitrite and Carbonate Ions

Resonance explains why some Lewis structures do not match the measured properties of a molecule or ion. When two or more Lewis structures have the same atom arrangement, the real electron distribution is an average of the structures shown. The nitrite anion, NO2−, is one example. It can be drawn in two ways, with the N–O and N=O bonds in different places. If nitrite had one single bond and one double bond, the two bond lengths should be different, because a double bond is shorter and stronger...

valence bond theory and hybridized orbitals

valence-bond-theory-and-hybridized-orbitals

Covalent Bond Overlap and Orbital Hybridization

Covalent bonds form when orbitals on two atoms overlap and their single electrons pair up. The bond is stronger when the overlap is greater. Maximum overlap happens when the orbitals meet along a direct line between the two nuclei. A sigma bond, or σ bond, is the kind of covalent bond found in a single bond in a Lewis structure. In a σ bond, electron density is concentrated along the internuclear axis. A pi bond, or π bond, forms when two p orbitals overlap side by side. In a π bond, the...

mo theory and covalent bonding

Bond Order and Molecular Orbitals

Molecular orbital theory explains how electrons are arranged in molecules. It treats electron regions in a molecule much like atomic orbitals in an atom. A molecular orbital is the region of space where a valence electron is most likely to be found. Molecular orbitals form through the linear combination of atomic orbitals, or LCAO. When atomic wave functions combine in phase, they create regions with high electron density. When they combine out of phase, they create nodes, or regions with no...

intermolecular forces and physical properties

intermolecular-forces-and-physical-properties

How Intermolecular Forces Affect Matter

Intermolecular forces are the attractions between molecules, and they help explain how matter behaves. These forces influence melting points, boiling points, and whether substances mix with one another. Water has a much higher boiling point than hexane, which shows that water has stronger intermolecular forces. Three main kinds of intermolecular interactions are covered here. They include ion-dipole forces, dipole-dipole interactions, and van der Waals forces, which include London dispersion...

solubility

Why Some Substances Dissolve in Water

Solution formation depends on how solutes and solvents interact. A solution is a homogeneous mixture made of a solvent, which is the larger part, and a solute, which is the smaller part. The physical state of a solution is usually the same as the solvent. Concentration is often described as dilute for a low amount of solute or concentrated for a high amount of solute. When a solute dissolves, its particles are surrounded by solvent species. This process is called solvation. If water is the...

introduction to functional groups

Functional Groups and Organic Molecules

Functional groups are groups of atoms with specific chemical properties that appear within organic molecules. They are sometimes shown as "R." These groups sit along the carbon backbone of macromolecules, which can form chains or rings of carbon atoms. Functional groups help functionalize a compound. That means they can give the molecule different physical and chemical properties. In organic chemistry, this change in group structure can strongly affect how a compound behaves. Common...

overview of advanced functional groups

Advanced Functional Groups in Organic Chemistry

Advanced functional groups are atom clusters in organic molecules that give those molecules specific chemical properties. They are sometimes shown as "R" in formulas. By changing the atoms attached to a carbon skeleton, a functional group can make a compound behave differently in physical and chemical reactions. This topic covers several major classes of organic compounds with advanced functional groups. Aromatic hydrocarbons include benzene. Phenol is another example and is also called...

key terms and concepts

Learn how atomic orbitals, shells, subshells, and the four quantum numbers describe electron arrangement in atoms through the quantum mechanical model.

Atomic Orbitals and Quantum Numbers | JoVE K12

organic chemistry

JoVE Core Organic Chemistry explains basic concepts of stereochemistry, reactions, and mechanisms using concise and easy-to-understand animated video lessons. Additionally, the scientist-in-action videos demonstrate the application of related concepts in classical and original research experiments performed in today's laboratories worldwide.

HS-PS1-2

HS-PS1-3

motion-and-stability-forces-and-interactions

Motion And Stability: Forces And Interactions

HS-PS2-6

Virginia  Standards of Learning

HIgh School

CH.2

CH.2.d

Next Generation Science Standards

Physical Science

Matter and Its Interactions

Florida Department of Education

SC.912.P.8

SC.912.P.8.5

south-carolina-college-and-career-ready-science-standards

South Carolina College and Career Ready Science Standards

C-PS1-1

C-PS1-3.

Motion and Stability: Forces and Interactions

C-PS2-6.

Physics

P-PS2-6.

The Periodic Table

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Periodic Classification of the Elements

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the-periodic-table-and-organismal-elements

The Periodic Table And Organismal Elements

Atomic Structure

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Electron Configurations

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An atom comprises protons and neutrons, which are contained inside the dense, central&#160;core called the nucleus, with electrons present around the ...

electron-configuration-of-multielectron-atoms

Electron Configuration of Multielectron Atoms

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atomic-radii-and-effective-nuclear-charge

Atomic Radii and Effective Nuclear Charge

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The Aufbau Principle and Hund's Rule

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Coulomb's Law

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Electric Charges

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sources-and-properties-of-electric-charge

Sources and Properties of Electric Charge

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Types of Forces

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Electric Fields

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Intermolecular Forces

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

Van der Waals Interactions

Atoms and molecules interact with each other through intermolecular forces. These electrostatic forces arise from attractive or repulsive interactions ...

Chemical Bonds


Atoms participate in a chemical bond formation&#160;to acquire a completed valence-shell electron configuration similar to that of the noble gas nearest ...

Electron Behavior

Electrons are negatively charged subatomic particles attracted to and orbit around the positively-charged nucleus of an atom. They reside in spaces ...

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 ...

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 the periodic table as a model to predict the relative properties of elements based on the patterns of electrons in the outermost energy level and the composition of the nucleus of atoms.  Clarification Statement: Chemistry: Examples of properties that could be predicted from patterns could include reactivity of metals, types of bonds formed, numbers of bonds formed, atomic radius, atomic mass, or reactions with oxygen. Emphasis is on main group elements and qualitative understanding of the relative trends of ionization energy and electronegativity.

Properties of Transition Metals

Transition metals are defined as those elements that have partially filled d orbitals. As shown in Figure 1, the d-block elements in groups 3&#8211;12 are ...

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 ...

Chemical Reactions

A chemical reaction is a process by which the bonds in the atoms of substances are rearranged to generate new substances. Matter cannot be created or ...

Chemical Equations

Chemical equations represent the identities and relative quantities of substances involved in a chemical reaction. The substances undergoing reaction are ...

Introduction to Chemical Reactions

All chemical reactions begin with a reactant, the general term for one or more substances entering the reaction. Sodium and chloride ions, for example, ...

Temperature Dependence on Reaction Rate

The Collision Theory
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stoichiometry-product-yield-and-limiting-reactants

Stoichiometry, Product Yield, and Limiting Reactants

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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

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Dynamic Equilibrium

A reversible chemical reaction represents a chemical process that proceeds in both forward (left to right) and reverse (right to left) directions. When ...

Construct and revise an explanation for the outcome of a simple chemical reaction based on the outermost electron states of atoms, trends in the periodic table, and knowledge of the patterns of chemical properties.  Clarification Statement: Chemistry: Examples of chemical reactions could include the reaction of sodium and chlorine, carbon and oxygen, or carbon and hydrogen. Reaction classification aids in the prediction of products (e.g. synthesis, decomposition, single displacement, double displacement, and acid-base).

Intermolecular vs Intramolecular Forces

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

comparison-between-electrical-and-gravitational-forces

Comparison Between Electrical And Gravitational Forces

There are four fundamental forces in nature: the gravitational force, the electromagnetic force, the strong nuclear force, and the weak nuclear force. To ...

Intermolecular Forces and Physical Properties



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

electric-field-of-two-equal-and-opposite-charges

Electric Field of Two Equal and Opposite Charges

Atoms generally contain the same number of positively and negatively charged particles, protons, and electrons. Hence, they are electrically neutral. ...

Electric Field

Consider two point charges, each exerting Coulomb force on the other. It is possible to describe the Coulomb interaction via an intermediate step by ...

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 ...

Electric Dipoles and Dipole Moment

Consider two charges of equal magnitude but opposite signs. If they cannot be separated by an external electric field, the system is called a permanent ...

Plan and conduct an investigation to gather evidence to compare the structure of substances at the macroscale to infer the strength of electrical forces between particles.  Clarification Statement: Emphasis is on understanding the strengths of forces between particles, not on naming specific intermolecular forces (such as dipole-dipole). Examples of particles could include ions, atoms, molecules, and network solids (such as graphite). Examples of macro-properties of substances could include the melting point and boiling point, vapor pressure, and surface tension.

bond-dissociation-energy-and-activation-energy

Bond Dissociation Energy and Activation Energy

Bond energy is the energy required to break a bond homolytically. These values are usually expressed in units of kcal/mol or kJ/mol and are referred to as ...

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, ...

Coupled Reactions

Cellular processes such as building and breaking down complex molecules occur through stepwise chemical reactions. Some of these chemical reactions are ...

energy-diagrams-transition-states-and-intermediates

Energy Diagrams, Transition States, and Intermediates

Free-energy diagrams, or reaction coordinate diagrams, are graphs showing the energy changes that occur during a chemical reaction. The reaction ...

What is Metabolism?

Overview

Metabolism represents all of the chemical activity in a cell, including reactions that build molecules (anabolism) and those that break ...

types-of-chemical-reactions-anabolic-and-catabolic

Types of Chemical Reactions: Anabolic and Catabolic

The first law of thermodynamics holds that energy can neither be created nor destroyed&#8212;it can only change form. An organism&#39;s essential function ...

Non-equilibrium in the Cell

An important concept in studying metabolism and energy is that of chemical equilibrium. Most chemical reactions are reversible. They can proceed in both ...

Activation Energy

Activation energy is the minimum amount of energy necessary for a chemical reaction to move forward. The higher the activation energy, the slower the rate ...

Energy Transfer in Chemical Reactions

Chemical reactions require sufficient energy to cause the matter to collide with enough precision and force that old chemical bonds can be broken and new ...

Develop a model to illustrate that the release or absorption of energy from a chemical reaction system depends upon the changes in total bond energy.  Clarification Statement: Emphasis is on the idea that a chemical reaction is a system that affects the energy change.  Examples of models could include molecular-level drawings and diagrams of reactions, graphs showing the relative energies of reactants and products, and representations showing energy is conserved.

HS-PS1-4

Atomic Orbitals and Quantum Numbers

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