Name: dialysis for buffer exchange in biochemistry
Uploaded: 2023-04-30T06:30:58.000Z
Duration: 5 min 26 s
Channel: JoVE

K12 Standards

new-york-state-science-learning-standards

New York State Science Learning Standards

High School

Physical Science

HS. Structure and Properties of Matter

HS-PS1-10.

Dialysis: Diffusion Based Separation

투석은 확산에 기초한 분자를 분리하기 위한 생화학에 사용되는 일반적인 기술입니다. 이 절차에서, 반투과성 막은 크기에 따라 특정 분자의 움직임을 허용합니다. 이 방법은 탈염으로 알려진 버퍼의 제거에 적용될 수 있고, 또는 단백질 용액으로부터 완충 분자 또는 이온을 교환할 수 있다.
이 비디오는 일반적인 절차와 함께 투석의 원리를 다룹니다.  투석의 몇몇 응용은 초원심 분리 다음 그라데이션 시약의 제거, 막 단백질 추출 후 세제 제거, 용액 환경을 변경하여 단백질의 재구성을 포함하여 검토됩니다.

이해 상충이 선언되지 않았습니다.

투석: 확산 기반 분리

투석은 확산에 기초한 분자를 분리하기 위한 생화학에 사용되는 일반적인 기술입니다. 이 절차에서, 반투과성 막은 크기에 따라 특정 분자의 움직임을 허용합니다. 이 방법은 탈염으로 알려진 버퍼의 제거에 적용될 수 있고, 또는 단백질 용액으로부터 완충 분자 또는 이온을 교환할 수 있다.
이 비디오는 일반적인 절차와 함께 투석의 원리를 다룹니다.  투석의 몇몇 응용은 초원심 분리 다음 그라데이션 시약의 제거, 막 단백질 추출 후 세제 제거, 용액 환경을 변경하여 단백질의 재구성을 포함하여 검토됩니다.
<div class="chapter_text" id="script_0">
생화학 적 샘플은 일반적으로 다운스트림 처리 및 분석을 방해 할 수있는 높은 완충농도를 갖는다. 투석은 확산에 기초하여 분자를 분리하는 데 사용되는 일반적, 저렴한 기술입니다. 이 방법은 크기에 따라 특정 성분의 움직임을 허용하는 반 투과성 멤브레인을 사용합니다. 이 비디오는 투석의 개념, 일반적인 절차 및 생화학에 대한 사용의 일부를 보여줍니다.
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<div class="chapter_text" id="script_1">
투석의 가장 중요한 측면은 분자량 컷오프를 부과하는 모공이 있는 반 투과성 멤브레인으로 특정 크기 미만의 분자가 통과할 수 있도록 합니다. 예를 들어, 10k 멤브레인은 일반적으로 10킬로달톤보다 큰 분자를 유지합니다. 그러나, 분자량 차단은 이산 또는 정확한 경계가 아닙니다. 멤브레인은 전형적으로 광범위한 기공 크기를 포함하므로 컷오프 근처의 분자의 작은 분수는 손실될 수 있습니다.
분자량 컷오프는 구형 단백질을 사용하여 정의되기 때문에, DNA 또는 RNA 같이 유사한 질량의 선형 분자는, 통해 미끄러질 수 있습니다. 멤브레인은 전형적으로 원하는 분자의 분자량의 1/1을 선택한다.
절차를 수행하기 위해 샘플은 멤브레인에 배치되며, 이는 투석이라고 하는 대량의 용액에 차례로 추가됩니다. 시간이 지남에 따라, 더 작은 분자는 샘플과 투석 사이 막을 통해 자유롭게 확산 될 것 이다, 더 큰 생체 분자 내에서 개최 하는 동안. 투석은 느린 과정입니다. 하룻밤 동안 또는 며칠 동안 실행되도록 허용하는 것이 일반적입니다.
투석물이 순수한 물인 경우, 전체 완충 농도가 감소하며, 탈염처리로 알려져 있습니다. 솔루션에 다른 작은 파티클이 포함되어 있으면 일부는 샘플로 이동하여 버퍼 교환으로 이어집니다. 투석은 평형 과정이기 때문에 투석은 소분자를 더 이상 대체하기 위해 여러 번 새로 고칠 수 있습니다. 프로세스가 완료되면 추가 처리를 위해 샘플을 다시 수집합니다.
투석의 기초를 보았으니 일반적인 절차를 살펴보겠습니다.
</div>
<div class="chapter_text" id="script_2">
절차를 시작하기 전에 멤브레인은 투석에 미리 담가됩니다. 이렇게 하면 사용하기 쉽고 방부제를 제거합니다. 일단 준비가 되면, 샘플은 일반적으로 주사기와 함께 수집되고 투석 용기에 추가됩니다. 이것은 맨손으로 튜브를 하거나 카세트 내에 포함될 수 있습니다. 초과 공기는 멤브레인으로 샘플의 표면적을 최대화하기 위해 투석 설정에서 제거됩니다. 그런 다음 확산을 최대화하기 위해 교반과 함께 투석에 설치됩니다. 교반을 억제하지 않도록 부동해야합니다.
투석은 시료와 투석 사이의 평형에 도달하면 관련 간격으로 변경됩니다. 마지막 변경 후, 반응은 일반적으로 하룻밤 실행 남아. 충분한 기간 이후에 버퍼가 없거나 교환된 샘플이 카세트에서 제거됩니다. 일단 수집되면, 실험의 특성에 따라 샘플을 분석하거나 추가로 처리할 수 있다.
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<div class="chapter_text" id="script_3">
이제 우리는 일반적인 투석 절차를 보았으니, 이 기술이 생화학에서 사용되는 방법 중 일부를 살펴보겠습니다.
밀도 그라데이션은 복잡한 생물학적 샘플을 분리하는 일반적인 방법입니다. 이 개념은 작은 입자, 일반적으로 자당 또는 염화물 이온에 분포에 의존한다. 완료되면 수집된 샘플을 처리하기 전에 이러한 시약을 제거해야 합니다. 투석은 향후 분석을 위해 정제된 샘플을 활용할 수 있게 합니다.
특정 단백질은 세포의 지질 이중층 내에서 발견되며, 일반적으로 리포솜으로 알려진 구형 지질 소포로 산재하여 연구됩니다. 단백질과 지질은 먼저 세제로 추출됩니다. 투석은 천천히 세제를 제거하기 위해 사용될 수 있으며, 프로테오올리포좀을 형성한다.
정화 후 일부 단백질은 잘못 접히거나 변성되어 기능저하를 초래합니다. 구조에 있는 이 변경을 일으키는 원인이 되는 화합물은 투석으로 제거될 수 있고, 기능성 점막의 재구성으로 이끌어 냅니다.
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<div class="chapter_text" id="script_4">
당신은 투석에 조브의 비디오를 보았다. 이제 이 확산 기반 방법, 간단한 실험 절차 및 이 기술의 사용을 이해해야 합니다.
시청해 주셔서 감사합니다!
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Dialysis is a common technique used in biochemistry for separating molecules based on diffusion. In this procedure, a semipermeable membrane allows the ...

생화학 시료는 일반적으로 다운스트림 처리 및 분석을 방해할 수 있는 높은 완충액 농도를 가지고 있습니다. 투석은 확산을 기반으로 분자를 분리하는 데 사용되는 일반적이고 저렴한 기술입니다. 이 방법은 크기에 따라 특정 구성 요소의 이동을 허용하는 반투과성 멤브레인을 사용합니다. 이 비디오는 투석의 개념, 일반적인 절차 및 생화학에서의 몇 가지 용도를 보여줍니다. 투석의 가장 중요한 측면은 반투과성 멤브레인으로, 분자량 차단을 부과하는 기공이 있어 특정 크기 미만의 분자가 통과할 수 있습니다. 예를 들어, 10k 멤브레인은 일반적으로 10킬로달톤보다 큰 분자를 유지합니다. 그러나 분자량 컷오프는 불연속적이거나 정확한 경계가 아닙니다. 멤브레인은 일반적으로 광범위한 공극 크기를 포함하므로 컷오프 근처의 분자 중 작은 부분이 손실될 수 있습니다. 분자량 컷오프는 구형 단백질을 사용하여 정의되기 때문에 DNA 또는 RNA와 같은 유사한 질량의 선형 분자가 빠져나갈 수 있습니다. 멤브레인은 일반적으로 원하는 분자의 분자량의 1/2에서 1/3로 선택됩니다. 절차를 수행하기 위해 샘플을 멤브레인에 넣고, 이 멤브레인은 다시 투석액이라고 하는 많은 양의 용액에 추가됩니다. 시간이 지남에 따라 더 작은 분자는 샘플과 투석액 사이의 멤브레인을 가로질러 자유롭게 확산되는 반면 더 큰 생체 분자는 그 안에 유지됩니다. 투석은 느린 과정입니다. 밤새 또는 여러 날에 걸쳐 실행되도록 허용하는 것이 일반적입니다. 투석액이 순수한 물인 경우 전체 완충액 농도가 감소하며, 이를 탈염이라고 합니다. 용액에 다른 작은 입자가 포함되어 있는 경우 일부는 샘플로 이동하여 버퍼 교환으로 이어집니다. 투석은 평형 과정이기 때문에 투석액을 여러 번 새로 고쳐 작은 분자를 더 많이 대체할 수 있습니다. 공정이 완료되면 추가 처리를 위해 샘플을 다시 수집합니다. 지금까지 투석의 기초에 대해 알아보았으니, 이제 일반적인 절차를 살펴보자. 절차를 시작하기 전에 멤브레인을 투석액에 미리 담급니다. 이렇게 하면 사용이 더 쉬워지고 방부제가 제거됩니다. 준비가 되면 일반적으로 주사기로 검체를 채취한 다음 투석 용기에 추가합니다. 이것은 베어 튜브이거나 카세트 내에 포함될 수 있습니다. 투석 설정에서 과도한 공기를 제거하여 멤브레인과 함께 샘플의 표면적을 최대화합니다. 그런 다음 확산을 최대화하기 위해 교반하면서 설정을 투석액에 넣습니다. 교반을 방해하지 않도록 떠 있어야 합니다. 투석액은 샘플과 투석액 사이의 평형에 도달함에 따라 적절한 간격으로 변경됩니다. 마지막 변경 후 반응은 일반적으로 밤새 실행되도록 둡니다. 충분한 시간이 지난 후, 버퍼가 없거나 교환된 샘플을 카세트에서 제거합니다. 일단 수집되면 실험의 성격에 따라 샘플을 분석하거나 추가 처리할 수 있습니다. 일반적인 투석 절차에 대해 살펴보았으니, 이제 이 기술이 생화학에서 어떻게 사용되는지 살펴보자. 밀도 구배는 복잡한 생물학적 샘플을 분리하는 일반적인 방법입니다. 이 개념은 일반적으로 자당 또는 염화 세슘 이온과 같은 작은 입자에 대한 분포에 의존합니다. 일단 완료되면, 수집된 샘플을 처리하기 전에 일반적으로 이러한 시약을 제거해야 합니다. 투석을 통해 정제된 검체를 향후 분석에 활용할 수 있습니다. 특정 단백질은 세포의 지질 이중층(lipid bilayer) 내에서 발견되며, 일반적으로 리포솜(liposome)으로 알려진 구형 지질 소포(spherical lipid vesicle)에 단백질을 산재하여 연구합니다. 단백질과 지질은 먼저 세제로 추출합니다. 투석을 사용하여 세제를 천천히 제거하여 프로테오리포좀을 형성할 수 있습니다. 정제 후 일부 단백질은 잘못 접히거나 변성되어 기능 손실로 이어집니다. 이러한 구조 변화를 일으키는 화합물은 투석으로 제거할 수 있으며, 이는 기능성 분석물질의 개질로 이어질 수 있습니다. 투석에 대한 JoVE의 비디오를 시청하셨습니다. 이제 이 확산 기반 방법, 간단한 실험 절차 및 이 기술의 사용법을 이해해야 합니다. 시청해 주셔서 감사합니다!

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dialysis for buffer exchange in biochemistry

Dialysis is a common biochemistry technique for buffer exchange and desalting. It separates molecules by diffusion through a semipermeable membrane, which lets small molecules pass while holding larger biomolecules inside the sample.

The membrane is the key part of the setup. Its pores create a molecular weight cutoff, so a membrane such as a 10 kDa membrane usually keeps molecules larger than 10 kilodaltons inside. This cutoff is not exact, because membranes have a range of pore sizes. Molecules near the cutoff can be lost, and linear molecules such as DNA or RNA may pass through more easily than globular proteins of the same mass. For that reason, membranes are often chosen at about one-half to one-third of the size of the molecule being kept.

To run dialysis, the sample is placed inside the membrane and then put into a large volume of solution called the dialysate. Over time, small molecules move across the membrane between the sample and the dialysate, while larger biomolecules stay in place. The process is slow, so it often runs overnight or even for several days. If the dialysate is pure water, the buffer level in the sample drops. This is called desalting. If the dialysate contains other small molecules, they can move into the sample, which creates buffer exchange. Because dialysis reaches equilibrium, the dialysate may be replaced several times to remove more small molecules.

A general dialysis procedure starts by presoaking the membrane in dialysate. This helps make the membrane easier to use and removes preservatives. The sample is then loaded with a syringe into tubing or a cassette. Excess air is removed to increase contact between the sample and the membrane. The setup is placed in dialysate with stirring so diffusion can continue efficiently. It should float so it does not block stirring. After the last dialysate change, the sample is usually left overnight and then collected for later analysis or further processing.

Dialysis is also useful in several biochemistry workflows. After density gradient separation, it can remove gradient reagents such as sucrose or cesium chloride ions before the sample is processed. It is also used after membrane protein extraction, where detergents are slowly removed to help form proteoliposomes from proteins and lipids. In another application, dialysis can remove compounds that caused proteins to misfold or denature, allowing the proteins to regain function in a new solution environment.

Dialysis for Buffer Exchange in Biochemistry

dialysis-for-buffer-exchange-in-biochemistry

dialysis: diffusion based separation

Dialysis is a common biochemistry technique for buffer exchange and desalting. It separates molecules by diffusion through a semipermeable membrane, which lets small molecules pass while holding larger biomolecules inside the sample. The membrane is the key part of the setup. Its pores create a molecular weight cutoff, so a membrane such as a 10 kDa membrane usually keeps molecules larger than 10 kilodaltons inside. This cutoff is not exact, because membranes have a range of pore sizes.

enzyme assays and kinetics

Measuring Enzyme Reaction Rates

Enzyme reaction rates can be measured with assays that track how substrate or product levels change over time. Enzymes are proteins, or sometimes RNAs, that speed up chemical reactions by lowering the activation energy needed to start them. They act on a specific substrate and help form a product that supports life processes. Enzymatic reactions are often described in three steps. First, the substrate binds to the enzyme active site and forms an enzyme-substrate complex. That complex can fall...

maldi-tof mass spectrometry

How MALDI-TOF Reads Biomolecules

MALDI-TOF mass spectrometry reads biomolecules by using a laser, a matrix, and a time-of-flight analyzer. MALDI, or matrix-assisted laser desorption ionization, helps fragile molecules keep their structure while they are moved into the mass analyzer. The analyzer then separates compounds based on size and charge. In MALDI, the sample is mixed into a matrix, usually an organic compound with aromatic and conjugated double bonds. A laser pulse strikes the spot, and the matrix absorbs most of the...

tandem mass spectrometry

Tandem Mass Spectrometry for Biomolecule Analysis

Tandem mass spectrometry is used to isolate a biomolecule and break it into smaller pieces so its makeup can be studied. Because biomolecules often have large, complex structures, it can be hard to identify their molecular composition and sequence from a single measurement. By linking mass spectrometers in series, the technique first selects one ion and then analyzes the fragments it produces. The process starts with an ion source that converts the sample into ions. A mass analyzer then...

protein crystallization

Protein Crystals for Structure Analysis

Protein crystals help scientists study protein structure and function. A crystal is a solid lattice made from purified protein molecules. These crystals are useful in structural biology because they reveal details that methods like mass spectrometry and SDS-PAGE cannot show on their own. Protein crystallization is paired with recombinant protein expression and x-ray diffraction to support this work. The process starts with a large amount of very pure protein. Researchers often make that...

chromatography-based biomolecule purification methods

chromatography-based-biomolecule-purification-methods

Protein Purification with SEC and IMAC

Protein purification with size-exclusion chromatography and affinity chromatography helps isolate biomolecules from complex mixtures. These methods are common in biochemistry because purified samples are needed before a biomolecule’s properties and activity can be studied. The video focuses on the principles behind size-exclusion chromatography, affinity chromatography, and immobilized metal affinity chromatography, or IMAC. Size-exclusion chromatography, or SEC, separates molecules by size. A...

two-dimensional gel electrophoresis

Protein Mapping with 2D Gel Electrophoresis

Protein mapping with 2D gel electrophoresis separates complex protein mixtures across two steps. The method combines isoelectric focusing, or IEF, with sodium dodecyl sulfate polyacrylamide gel electrophoresis, or SDS-PAGE. Together, these methods can resolve thousands of biomolecules from a single sample by their isoelectric point and molecular weight. The first dimension is IEF. Each protein has an isoelectric point, or pI, which is the pH where its net charge is zero. Proteins are loaded...

metabolic labeling

Tracking Cell Chemistry with Metabolic Labels

Metabolic labeling tracks cell chemistry by using chemical analogs that cells take up and build into biomolecules. These labels help scientists follow biochemical changes and modifications inside cells. The labeled products can then be studied with tools such as SDS-PAGE and NMR to learn more about metabolic pathways. Several labeling strategies are shown here. Isotopic labeling uses analogs that match the natural molecule but contain uncommon isotopes, such as carbon-13 and nitrogen-15 in an...

electrophoretic mobility shift assay (emsa)

electrophoretic-mobility-shift-assay-emsa

Detecting Protein-DNA Binding by EMSA

Electrophoretic mobility shift assay, or EMSA, is a biochemical method used to detect binding between proteins and nucleic acids. It is also called a gel shift assay. The test compares how a labeled nucleic acid moves through a gel before and after it binds a protein. EMSA is used to see whether a specific protein binds to a specific nucleic acid. First, the nucleic acid is labeled to make a probe. The transcript describes radioactive phosphorus-32 as a common label. The probe is then mixed...

photometric protein determination

Measuring Protein Concentration with Absorbance

Measuring protein concentration with absorbance is a key step in many biochemical assays. Photometric methods use the fact that samples with more light-absorbing material transmit less light. Because concentration and absorption are directly related, this makes it possible to measure an unknown sample. The core idea comes from the Beer-Lambert Law. This law states that the concentration of a light-absorbing species is proportional to its absorbance. The video also introduces the Bradford assay...

density gradient ultracentrifugation

Sucrose Gradient Separation in an Ultracentrifuge

Sucrose gradient separation in an ultracentrifuge is a lab method for isolating cell parts and biomolecules. It uses differences in density to make particles sink or rise in a liquid. A high-speed ultracentrifuge speeds up this process so components can be separated without destroying them. The basic idea starts with a suspension, which is particles mixed in a liquid solvent. Particles that are denser than the solvent sediment, while less dense particles float. A rotor inside the...

co-immunoprecipitation and pull-down assays

co-immunoprecipitation-and-pull-down-assays

Protein Interaction Capture Methods in Cells

Co-immunoprecipitation and pull-down assays are laboratory methods used to capture stable protein-protein interactions. Protein-protein interactions help control many biological functions, but many of them have not yet been identified. These assays are related to immunoprecipitation, which isolates a target protein from a mixed sample using an antibody. In co-immunoprecipitation, or CoIP, an antibody binds the target protein, and that protein is already attached to another protein that the...

reconstitution of membrane proteins

Membrane Proteins in Liposome Models

Membrane proteins can be moved into liposome models so their function can be studied outside a cell. Reconstitution means restoring an isolated biomolecule to a working form. For membrane proteins, that usually means placing a purified protein into an artificial lipid membrane. Cell membranes are made mainly of phospholipids and membrane proteins. The phospholipids form a bilayer with hydrophilic phosphate heads facing water and hydrophobic fatty acid tails facing inward. Some membrane...

f&#246;rster resonance energy transfer (fret)

FRET as a Molecular Ruler in Cells

Föster resonance energy transfer, or FRET, is a way to study close-range biochemical interactions using light-emitting molecules. A donor fluorophore can pass energy to an acceptor fluorophore when their emission and absorption spectra overlap. This transfer happens only when the pair is very close together, usually within 10 nm. Because FRET depends on distance, it is often called a molecular or spectroscopic ruler. The strength of the signal is measured as FRET efficiency, which describes...

surface plasmon resonance (spr)

SPR Biosensors for Tracking Binding Kinetics

Surface plasmon resonance, or SPR, is a way to track biomolecular binding on a label-free biosensor. It is used to measure molecular affinity, kinetics, specificity, and concentration. The method works with a thin metal layer on a prism, where changes in reflected light reveal interactions in real time. SPR sensors use a thin layer of a noble metal on the face of a prism. Light is reflected from the prism-metal interface into a photodetector. At one specific angle, called the surface plasmon...

biochemistry

이 컬렉션은 선호도 크로마토그래피와 같은 일반적으로 사용되는 정제 방법과 MALDI-TOF와 같은 분석 방법을 제공합니다. 또한, 비디오는 공동 면역 침전 및 대사 라벨링과 같은 생체 분자 상호 작용 및 기능을 평가하는 방법을 선보이고 있습니다.

Learn how dialysis uses a semipermeable membrane to remove small molecules, exchange buffers, and support biochemistry workflows like desalting and protein recovery.

Dialysis for Buffer Exchange in Biochemistry | JoVE K12

Life Science

matter-and-energy-in-organisms-and-ecosystems

Matter and Energy in Organisms and Ecosystems

HS-LS1-6.

Overview

Principles of Dialysis

Dialysis Procedure

Applications

Summary

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 ...

Electron Orbital Model

Orbitals are the areas outside of the atomic nucleus where electrons are most likely to reside. They are characterized by different energy levels, shapes, ...

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 ...

Coordination Chemistry Complexes

Source: Laboratory of Dr. Neal Abrams &#8212; SUNY College of Environmental Science and Forestry
Transition metals are found everywhere from vitamin ...

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 of atoms.

HS-PS1-1.

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:


	...

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 ...

VSEPR Theory and the Basic Shapes

Overview of VSEPR Theory

Valence shell electron-pair repulsion theory (VSEPR theory) enables us to predict the molecular structure, including approximate ...

vsepr-theory-and-the-effect-of-lone-pairs

VSEPR Theory and the Effect of Lone Pairs

Effect of Lone Pairs of Electrons&nbsp;on Molecule Geometry

It is important to note that electron-pair geometry around a central atom is not the same ...

Predicting Molecular Geometry

VSEPR Theory for Determination of Electron Pair Geometries

The following procedure uses VSEPR theory to determine the electron pair geometries and the ...

Molecular Shape and Polarity

Dipole Moment of a Molecule

Polar covalent bonds connect two atoms with differing electronegativities, leaving one atom with a partial positive charge ...

Valence Bond Theory

Overview of Valence Bond Theory

Valence bond theory describes a covalent bond as the overlap of half-filled atomic orbitals (each containing a single ...

Hybridization of Atomic Orbitals I

The mathematical expression known as the wave function, &#x3C8;, contains information about each orbital and the wavelike properties of electrons in an ...

Hybridization of Atomic Orbitals II

sp3d and sp3d&nbsp;2 Hybridization

To describe the five bonding orbitals in a trigonal bipyramidal arrangement, we must use five of the valence shell ...

Molecular Orbital Theory I

Overview of Molecular Orbital Theory

Molecular orbital theory describes the distribution of electrons in molecules in the same way as the distribution of ...

Molecular Orbital Theory II

Molecular Orbital Energy Diagrams

The relative energy levels of atomic and molecular orbitals are typically shown in a molecular orbital diagram. For a ...

Molecular Orbital (MO) Theory

Source: Tamara M. Powers, Department of Chemistry, Texas A&#38;M University
This protocol serves as a guide in the synthesis of two metal complexes ...

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 ...

Molecular and Ionic 
Solids

Crystalline solids are divided into four types: molecular, ionic, metallic, and covalent network based on the type of constituent units and their ...

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, ...

Plan and conduct an investigation to gather evidence to compare the structure of substances at the bulk scale to infer the strength of electrical forces between particles.

HS-PS1-3.

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 ...

Biological Effects of Radiation

All radioactive nuclides emit high-energy particles or electromagnetic waves. When this radiation encounters living cells, it can cause heating, break ...

determining-rate-laws-and-the-order-of-reaction

Determining Rate Laws and the Order of Reaction

Source: Laboratory of Dr. Neal Abrams &#8212; SUNY College of Environmental Science and Forestry
All chemical reactions have a specific rate defining the ...

Develop models to illustrate the changes in the composition of the nucleus of the atom and the energy released during the processes of fission, fusion, and radioactive decay.

HS-PS1-8.

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 ...

Coordination Compounds and Nomenclature

In most main group element compounds, the valence electrons of the isolated atoms combine to form chemical bonds that satisfy the octet rule. For ...

Metal-Ligand Bonds

The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain ...

Coordination Number and Geometry

For transition metal complexes, the coordination number determines the geometry around the central metal ion. Table 1 compares coordination numbers to ...

physical-properties-of-minerals-i-crystals-and-cleavage

Physical Properties Of Minerals I: Crystals and Cleavage

Source: Laboratory of Alan Lester - University of Colorado Boulder
The physical properties of minerals comprise various measurable and discernible ...

Communicate scientific and technical information about why the particulate-level structure is important in the functioning of designed materials.

HS-PS2-6.

Dialysis for Buffer Exchange in Biochemistry

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Transcript

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