Name: separating liquids by boiling point
Uploaded: 2023-04-30T06:32:03.000Z
Duration: 10 min 9 s
Channel: JoVE

K12 Standards

new-york-state-science-learning-standards

New York State Science Learning Standards

High School

Physical Science

HS. Chemical Reactions

HS-PS1-5.

Fractional Distillation

1. Set-up of Fractional Distillation Apparatus
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Fractional Distillation Apparatus</td>
			<td>Quantity</td>
		</tr>
		<tr>
			<td>Retort stands (ring stands)</td>
			<td>2</td>
		</tr>
		<tr>
			<td>Screw jack</td>
			<td>1</td>
		</tr>
		<tr>
			<td>Clamps</td>
			<td>4</td>
		</tr>
		<tr>
			<td>Keck clamps</td>
			<td>4</td>
		</tr>
		<tr>
			<td>Magnetic stir bar</td>
			<td>1</td>
		</tr>
		<tr>
			<td>Fractionating column</td>
			<td>1</td>
		</tr>
		<tr>
			<td>“Y” adaptor</td>
			<td>1</td>
		</tr>
		<tr>
			<td>Thermometer & Thermometer Adaptor</td>
			<td>1</td>
		</tr>
		<tr>
			<td>100-mL round bottom flask</td>
			<td>1</td>
		</tr>
		<tr>
			<td>Condenser with water inlet and outlet tubes</td>
			<td>1</td>
		</tr>
		<tr>
			<td>Collection adaptor</td>
			<td>1</td>
		</tr>
		<tr>
			<td>25-mL graduated cylinders</td>
			<td>3</td>
		</tr>
		<tr>
			<td>Heating mantle</td>
			<td>1</td>
		</tr>
		<tr>
			<td>Stir plate</td>
			<td>1</td>
		</tr>
	</tbody>
</table>
Table 1. Fractional distillation apparatus components. 
Note: all glassware, with the exception of the graduated cylinders, should have ground-glass joints
<ol>
	<li>Gather all of the equipment needed to assemble the fractional distillation apparatus (Table 1) and place them in a fume hood.</li>
	<li>Place the heating mantle and stir plate at the foot of the retort stand, sitting on top of a screw jack.</li>
	<li>Using the screw jack, elevate the heating mantle to a height of 20 cm.</li>
	<li>Attach a clamp on the retort stand. Secure the round-bottom flask to the retort stand using the clamp so that the flask sits snuggly in the heating mantle.</li>
	<li>Remove the screw jack and the heating mantle, putting them aside for later.</li>
	<li>Add a magnetic stir bar to the round-bottom flask.</li>
	<li>Add a fractionating column to the top of the round-bottom flask, securing it to the retort stand with a clamp.</li>
	<li>Add a "Y" adaptor to the top of the fractionating column, securing it to the retort stand with a clamp and to the fractionating column with a Keck clip.</li>
	<li>Add a condensing column to the downward sloping arm of the "Y" adaptor, securing it with a Keck clip. For additional stability, the condenser can be secured with a clamp to a second retort stand.</li>
	<li>Connect tubing from the water source to the lower connection on the condenser and attach the water return tube to the higher connection on the condenser. Ensure the tubing is securely fitted to the condenser (consider using copper wire to hold the tubing in place).</li>
	<li>Connect a collection adaptor to the open end of the condenser and secure the connection with a Keck clip.</li>
	<li>Have three 25 mL graduated cylinders available for collection of the distillate.</li>
</ol>
<img alt="Distillation process diagram; lab setup with fractionating column, condenser, and flask." src="/files/ftp_upload/5700/5700fig5.jpg" data-altupdatedat="1761830439000" data-alt="Figure 5"> 
Figure 5. Apparatus for fractional distillation.
2. Preparation for the Distillation
<ol>
	<li>Remove the round bottom flask from the assembly by lowering it to the base of the retort stand.</li>
	<li>Place a stemmed funnel into the top of the round-bottom flask, and add the liquid to be distilled. Do not fill the flask more than half full.</li>
	<li>After filling the flask, remove the funnel.</li>
	<li>Raise the flask once again and place the flask back in its original position on the retort stand.</li>
	<li>Using the thermometer adaptor, place the thermometer into the remaining open port on the "Y" adaptor. The thermometer should be added last, as it is most susceptible to breakage.</li>
	<li>Position the bulb of the thermometer so that it is just below the side arm of the "Y" adaptor. This ensures an accurate reading of the vapor temperature.</li>
	<li>Replace the heating mantle and screw jack to their original position, snuggly enveloping the round-bottom flask.</li>
	<li>Place a graduated cylinder underneath the condenser adaptor, ready to collect the distillate.</li>
</ol>
3. Performing the Distillation
<ol>
	<li>Increase the temperature of the heating mantle gradually until the liquid in the round-bottom flask begins boiling.</li>
	<li>As soon as boiling commences, hold the temperature for 2 min.</li>
	<li>Note the ring of condensate rising slowly up the fractionating column. The rise should be gradual, which ensures proper separation of the mixture components across the theoretical plates. If the ring of condensate stops rising, increase the temperature slightly. It should take at least 5 min for the ring to reach the top of the column.</li>
	<li>Once the first drops of liquid start to fall down the condenser, the temperature should remain nearly constant. Record the temperature as each 2 mL of distillate collects in the graduated cylinder.</li>
	<li>Adjust the heat accordingly to allow for 1—2 drops/s from the condenser into the graduated cylinder.</li>
	<li>Each time the graduated cylinder reaches 4 mL, quickly replace it with an empty one.</li>
	<li>Pour the distillate into a clean, labeled vial for safekeeping.</li>
	<li>If the distillation is occurring very slowly, wrap the column with aluminum foil or glass wool to protect it from cold drafts.</li>
	<li>When the temperature begins to drop significantly, nearly all the cyclohexane has been distilled. Increase the temperature until the toluene starts to boil and distill. Again, record the temperature as each 2 mL of distillate collects.</li>
	<li>Before the entire content of the flask evaporates, stop heating the flask. It is important to ensure that the flask does not become dry, which might cause it to crack.</li>
	<li>Remove the heating mantle by lowering the screw jack to the base of the retort stand</li>
	<li>Analyze the contents of the vials of distillate to confirm the purity using a chosen technique, such as 1H NMR spectroscopy.</li>
</ol>

Destillatie is goed voor ongeveer 95 % van alle huidige industriële scheidingsprocessen. Het belangrijkste verschil tussen distillaties die op laboratoriumschaal worden uitgevoerd en die op industriële schaal is dat de eerste meestal batchgewijs worden uitgevoerd, terwijl de laatste vaak continu worden uitgevoerd. Bij continue destillatie worden het uitgangsmengsel, de dampen en het destillatieproduct constant van samenstelling gehouden door zorgvuldig het uitgangsmateriaal aan te vullen en fracties uit zowel het gas als...

fractionele destillatie

Bron: Laboratorium van Dr. Nicholas Leadbeater — Universiteit van Connecticut 
Destillatie is misschien wel de meest gebruikte laboratoriumtechniek die chemici toepassen voor het zuiveren van organische vloeistoffen. Verbindingen in een mengsel met verschillende kookpunten scheiden zich af in afzonderlijke componenten wanneer het mengsel zorgvuldig wordt gedistilleerd. De twee hoofdtypen destillatie zijn "eenvoudige destillatie" en "fraktionele destillatie", en beide worden veel gebruikt in organische chemielaboratoria.
Eenvoudige destillatie wordt gebruikt wanneer de vloeistof (a) relatief zuiver is (niet meer dan 10% vloeistofverteringen bevat), (b) een niet-vluchtig bestanddeel heeft, zoals een vast verontreinigingsmiddel, of (c) gemengd is met een andere vloeistof met een kookpunt dat met ten minste 25 °C verschilt. Fraktionele destillatie wordt gebruikt bij het scheiden van mengsels van vloeistoffen waarvan de kookpunten meer op elkaar lijken (minder dan 25 °C verschil).
Deze video beschrijft de fraktionele destillatie van een mengsel van twee veel voorkomende organische oplosmiddelen, cyclohexaan en tolueen.

Fractionele destillatie van een cyclohexaan-tolueen mengsel
De zuiverheid van het destillatieproduct kan worden beoordeeld met behulp van een aantal technieken. Een van de beste is NMR-spectroscopie. Het 1H-NMR spectrum van het oorspronkelijke mengsel vóór de destillatie wordt getoond in Figuur 6. Signalen voor zowel tolueen als cyclohexaan zijn duidelijk zichtbaar. 1HNMR-s...

Fractionele destillatie

Source: Laboratory of Dr. Nicholas Leadbeater &#8212; University of Connecticut&#160;
Distillation is perhaps the most common laboratory technique ...

Destillatie is een van de meest gebruikte technieken voor het zuiveren van vloeistoffen in laboratoriumomgevingen en is goed voor maximaal 95% van alle industriële scheidingsprocessen.Deze methode scheidt en zuivert vloeistoffen op basis van hun vluchtigheid, of de neiging van hun moleculen om uit de vloeibare fase te ontsnappen als gasvormige damp. Om een oplossing te distilleren, wordt deze verhit tot de meest vluchtige verbindingen beginnen te verdampen. De resulterende dampen worden vervolgens gecondenseerd tot een gezuiverde vloeistof, bekend als het distillaat, en verzameld.De meest gebruikelijke destillatiemethoden zijn: eenvoudige destillatie, die slechts één verdamping-condensatiecyclus gebruikt, en fractionele destillatie, die meerdere verdamping-condensatiecycli gebruikt.Deze video bespreekt de principes achter eenvoudige en fractionele destillatie, typische laboratoriumdestillatieapparaten en demonstreert een voorbeeld van een fractionele destillatieprocedure. Ten slotte worden toepassingen van destillatie behandeld.Wanneer een vloeistof wordt verhit, neemt de kinetische energie van zijn moleculen toe, waardoor sommige van de moleculen overgaan van de vloeibare in de gasvormige toestand. Dit proces, genaamd verdamping, verhoogt de dampdruk boven de vloeistof ten opzichte van de atmosferische druk. De temperatuur waarbij de dampdruk van de vloeistof gelijk is aan de luchtdruk van de omgeving, waarop 'bubbels' van damp zich in de vloeistof vormen, staat bekend als het kookpunt. Boven deze temperatuur zal de vloeistof volledig verdampen tot een gas.Bij een eenvoudige destillatie wordt een mengsel verhit in een kolf, en de resulterende dampen gaan door een condenseerkolom waar ze worden gekoeld en gecondenseerd tot een vloeistof, het distillaat genaamd, en worden verzameld. Deze methode gebruikt slechts één verdamping-condensatiecyclus en genereert zuivere distillaten uit zowel mengsels van vloeistoffen en vaste stoffen als mengsels van vloeistoffen met sterk verschillende kookpunten.Mengsels van vloeistoffen met kookpunten die verschillen met minder dan ongeveer 30 °C kunnen niet volledig worden gescheiden met eenvoudige destillatie. De samenstelling van het distillaat kan echter worden voorspeld met behulp van een 'kookpunt-diagram', dat temperatuur geeft als functie van de samenstelling van de vloeistof en de damp. Bijvoorbeeld, een gelijke mengsel van cyclohexaan en tolueen heeft een kookpunt van 90 °C, resulterend in een dampsamenstelling van 80% cyclohexaan en 20% tolueen, en opleverend een 80% zuiver distillaat.Het kookpuntdiagram voorspelt dat een tweede verdamping-condensatiecyclus, bereikt door het 80:20 distillaat te koken op ongeveer 84 °C, resulteert in een zuiverheid van 95%. Elke opeenvolgende cyclus, aangeduid als een 'theoretische plaat', verhoogt de zuiverheid van het, waarbij 3 theoretische platen resulteren in een zuiverheid van 99%. Hoewel het mogelijk is om dit te genereren door meerdere 'eenvoudige destillatie' apparaten aan elkaar te rijgen, bereikt 'fractionele destillatie' dit efficiënter.De opstelling voegt een 'fractioneerkolom' toe, tussen de startkolf en de condensor. Deze kolom is meestal gevuld met glazen kralen of metaalwol, wat een grote oppervlakte biedt voor de vloeistof om te condenseren en herhaaldelijk opnieuw te verdampen. Dit genereert een groot aantal theoretische platen.Terwijl dampen door de kolom stijgen, vormt zich een ring van condensaat en beweegt langzaam omhoog terwijl de dampen zich over de theoretische platen scheiden. Wanneer de damp de top van de kolom bereikt, gaan de moleculen met de hoogste vluchtigheid de condensor in waar ze worden verzameld als een hoogzuiver distillaat.Nu we de basisprincipes van destillatie hebben besproken, laten we een voorbeeld doorlopen voor een cyclohexaan: tolueen mengsel.Begin met het samenstellen van de componenten van het fractionele destillatie-apparaat in de afzuigkap. Plaats de verwarmingsmantel en roerplaat bovenop de laboratoriumkrik aan de voet van de retortstandaard en verhoog alles 8 inch met de krik.Bevestig drie klemmen aan de retortstandaard. Plaats de ronde bodemkolf zodat deze strak in de verwarmingsmantel past en bevestig deze aan de retortstandaard.Voeg een magnetische roerstaaf toe aan de kolf, plaats de fractioneerkolom erop en bevestig deze.Pass de 'Y'-adapter in de bovenkant van de fractioneerkolom. Bevestig deze aan de retortstandaard met een klem en bevestig vervolgens de grindglasverbinding tussen deze en de fractioneerkolom met een keckklem.Pass de condensor in de naar beneden schuine arm van de 'Y'-adapter en bevestig de verbinding. Voor extra stabiliteit klemmen de condensiekolom aan een tweede retortstandaard.Verbind een buis van de waterbron naar de onderste verbinding op de condensor. Verbind een tweede buis van de bovenste condensorverbinding naar de waterretourpoort.Bevestig de bekleding, zet het water aan en controleer of water door de condensor stroomt.Voeg een opvangadapter toe aan de condensiekolom. Bevestig deze verbinding met een keckklem en plaats een graduleerde cilinder eronder.Voordat u de thermometer installeert, laat de kolf zakken. Gebruik een trechter om minder dan de helft van de kolf te vullen met het startmengsel.Til de kolf omhoog, plaats deze weer in de fractioneerkolom en bevestig deze. Bevestig deze laatste grindglasverbinding met een keckklem en plaats vervolgens de krik en verwarmingsmantel terug op hun plaats.Pass tenslotte de thermometer in een adapter en plaats deze in de resterende poort van de 'Y'-adapter. Pas de hoogte van de thermometerbol aan, plaats deze net onder de zijarm van de 'Y'-adapter om nauwkeurige damptemperatuurmetingen te garanderen.Zet de hotplate aan, verhoog geleidelijk de temperatuur en verwarm de mantel tot het startmengsel begint te koken. Pas de temperatuur van de hotplate aan zoals nodig is om ervoor te zorgen dat het mengsel blijft koken, met een constante damptemperatuur gedurende de eerste 2 min? van de destillatie.Bekijk hoe de condensatiering zich vor

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Organische chemie

separating liquids by boiling point

Fractional distillation separates liquid mixtures by using differences in boiling point. Chemists use this lab technique to purify organic liquids. When a mixture is carefully distilled, compounds with different boiling points split into individual parts.

There are two main types of distillation: simple distillation and fractional distillation. Simple distillation is used when a liquid is relatively pure, when it contains no more than 10% liquid contaminants, or when it has a non-volatile component such as a solid impurity. It also works when two liquids differ in boiling point by at least 25 °C.

Fractional distillation is used when the liquids in a mixture have more similar boiling points. In these cases, the boiling points are separated by less than 25 °C. The video shows this method with cyclohexane and toluene, two common organic solvents.

Separating Liquids by Boiling Point

introduction to catalysis

Catalysis in Industry and Sustainability

Catalysis is a major part of modern technology. It helps chemical reactions happen by lowering activation energy, which is the energy needed to start a reaction. Catalysts can also affect selectivity, or which products form during a reaction. Catalysis has a large impact on industry and daily life. It is linked to about 35% of global GDP. It also supports the food supply for about 33% of the world’s population through fertilizers made by the Haber process. Because catalysts improve how...

assembly of a reflux system for heated chemical reactions

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Reflux Setup for Heating Reactants Safely

A reflux setup lets chemists heat reactants without losing material to evaporation. Many chemical experiments need elevated temperatures before a reaction starts. When the reactants or solvent have low boiling points, heating can cause them to escape as vapor. A reflux system prevents that loss by condensing the vapor that forms during heating. The condensed liquid then flows back into the reaction vessel. This keeps the reactants and solvent in the flask while the reaction is heated.

conducting reactions below room temperature

conducting-reactions-below-room-temperature

Cooling Baths for Low-Temperature Reactions

Low-temperature reactions are often run with cooling baths to keep the reaction flask below room temperature. Chemists use this setup when they want a reaction to stay within a specific temperature range. The reagents in the flask do not touch the cooling bath itself. Reaction rate depends on molecular collisions. At higher temperatures, atoms and molecules move faster, collide more often, and react more effectively. A common rule of thumb based on the Arrhenius equation says that raising the...

schlenk lines transfer of solvents

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degassing liquids with freeze-pump-thaw cycling

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Freeze-Pump-Thaw for Removing Dissolved Gases

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preparing anhydrous reagents and equipment

preparing-anhydrous-reagents-and-equipment

Moisture-Free Setup for Organic Reactions

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purifying compounds by recrystallization

Recrystallization for Solid Compound Purity

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separation of mixtures via precipitation

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solid-liquid extraction

Solvent Separation in Solid Samples

Solid samples can be prepared for chemical analysis by moving the target analyte into a liquid. This solid-liquid extraction step is used in many chemical analyses before spectroscopic or chromatographic identification and quantification. It helps separate the analyte from the rest of the sample matrix, which is the material surrounding it. A simple approach is to mix the solid with a solvent that can dissolve the analyte. Agitation helps the analyte leave the solid and partition into the...

rotary evaporation to remove solvent

Rotovap Use in Organic Chemistry

Rotary evaporation is a common lab method for drying and purifying samples in organic chemistry. It helps remove a solvent from a compound of interest when the compound has a higher boiling point. A rotary evaporator is often called a rotovap. The rotovap was invented in 1950 by the chemist Lyman C. Craig. It is widely used because it works quickly and can handle large volumes of solvent. For this reason, many laboratories prefer rotary evaporation when they need to remove low boiling point...

fractional distillation

Fractional distillation separates liquid mixtures by using differences in boiling point. Chemists use this lab technique to purify organic liquids. When a mixture is carefully distilled, compounds with different boiling points split into individual parts. There are two main types of distillation: simple distillation and fractional distillation. Simple distillation is used when a liquid is relatively pure, when it contains no more than 10% liquid contaminants, or when it has a non-volatile...

growing crystals for x-ray diffraction analysis

growing-crystals-for-x-ray-diffraction-analysis

X-ray Crystal Growth for Structure Analysis

X-ray crystal growth is a key step in X-ray crystallography, the method used to determine the spatial arrangement of atoms in a crystalline solid. That structure reveals the three-dimensional shape of a molecule or complex. Since structure and function are closely linked, this information can help explain a compound's behavior and reactivity. X-ray crystallography is one of the most useful ways to solve a compound's three-dimensional structure. In some cases, it may be the only practical...

performing 1d thin layer chromatography

Thin Layer Chromatography for Mixture Separation

Thin layer chromatography separates mixtures of non-volatile compounds. It uses a TLC plate with a thin layer of adsorbent material as the stationary phase. The adsorbent layer is fixed to a solid support such as plastic, aluminum, or glass. The sample and a reference compound are first dissolved in a suitable solvent. They are then applied as small spots near the bottom edge of the TLC plate. This placement helps the compounds move with the developing solvent in a controlled way. To run the...

column chromatography

Purifying Compounds with a Chromatography Column

Column chromatography is a useful method for purifying compounds. It uses a stationary phase packed into a column and a mobile phase that flows through it. The separation works because different molecules have different polarities, so they move through the column at different rates. The most common stationary phases are silica gel, or SiO2, and alumina, or Al2O3. The mobile phase is usually an organic solvent. The solvent choice depends on the polarity of the molecules being purified. More...

nuclear magnetic resonance (nmr) spectroscopy

nuclear-magnetic-resonance-nmr-spectroscopy

Using NMR to Track Organic Reactions

Nuclear magnetic resonance (NMR) spectroscopy helps organic chemists study molecules and check reaction results. It can show molecular structure, sample content, and sample purity. Because NMR is non-destructive, it is useful when the sample needs to be recovered after analysis. One of the most common methods is proton, or 1H, NMR. Protons in a molecule respond differently depending on their chemical environment. That difference makes it possible to infer the structure of the molecule from the...

organic chemistry

This collection features techniques routinely used in the organic chemistry lab, focusing on regulating temperature and atmosphere during chemical reactions and post-reaction refinement.

See how fractional distillation separates liquid mixtures with close boiling points. Learn why chemists use it for organic solvents like cyclohexane and toluene.

Separating Liquids by Boiling Point | JoVE K12

Earth and Space Sciences

Human Sustainability

HS-ESS3-2.

Overview

Principles of Simple and Fractional Distillation

Fractional Distillation Apparatus Setup

Purifying a Mixture by Fractional Distillation

Applications

Summary

The Periodic Table

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Alkali Metals

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Halogens

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Noble Gases


The elements in group 18 are noble gases (helium, neon, argon, krypton, xenon, and radon). They earned the name &ldquo;noble&rdquo; because they were ...

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Physical and Chemical Properties of Matter

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Types of Chemical Bonds

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Lewis Symbols and the Octet Rule

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Ionic Bonding and Electron Transfer

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Trends in Lattice Energy: Ion Size and Charge

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Covalent Bonding and Lewis Structures

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Electronegativity

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Bond Polarity, Dipole Moment, and Percent Ionic Character

Bond Polarity

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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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Lewis Structures of Molecular Compounds and Polyatomic Ions

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Assembly of a Reflux System for Heated Chemical Reactions

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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 ...

Conducting Reactions Below Room Temperature

Source: Laboratory of Dr. Dana Lashley - College of William and Mary
Demonstration by: Matt Smith
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Formal Charges

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Coordination Chemistry Complexes

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Exceptions to the Octet Rule

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	...

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Determining Rate Laws and the Order of Reaction

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Bond Energies and Bond Lengths

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Determining the Empirical Formula

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Determining the chemical formula of a compound is at the heart ...

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 ...

determining-the-solubility-rules-of-ionic-compounds

Determining the Solubility Rules of Ionic Compounds

Source: Laboratory of Dr. Neal Abrams &#8212; SUNY College of Environmental Science and Forestry
An ionic compound&#39;s solubility can be determined via ...

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 ...

Introduction to Catalysis

Source: Laboratory of Dr. Ryan Richards &#8212; Colorado School of Mines
Catalysis is among the most important fields of modern technology and presently ...

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 ...

Introduction to Titration

Source: Laboratory of Dr. Yee Nee Tan &#8212; Agency for Science, Technology, and Research
Titration is a common technique used to quantitatively ...

Le Ch&#226;telier's Principle

Source: Laboratory of Dr. Lynne O&#39;Connell &#8212; Boston College
When the conditions of a system at equilibrium are altered, the system responds in ...

Preparing Anhydrous Reagents and Equipment

Source: Laboratory of Dr. Dana Lashley - College of William and Mary
Demonstrated by: Timothy Beck and Lucas Arney
Many reactions in organic chemistry are ...

Proton Exchange Membrane Fuel Cells

Source: Laboratories of Margaret Workman and Kimberly Frye - Depaul University
The United States consumes a large amount of energy &#8211; the current ...

Solutions and Concentrations

Source: Laboratory of Dr. Michael Evans &#8212; Georgia Institute of Technology
A solution is a homogeneous mixture containing some components in small ...

spectrophotometric-determination-of-an-equilibrium-constant

Spectrophotometric Determination of an Equilibrium Constant

Source: Laboratory of Dr. Michael Evans &#8212; Georgia Institute of Technology
The equilibrium constant, K, for a chemical system is the ratio of product ...

using-differential-scanning-calorimetry-to-measure-changes-in-enthalpy

Using Differential Scanning Calorimetry to Measure Changes in Enthalpy

Source: Laboratory of Dr. Terry Tritt &#8212; Clemson University
Differential Scanning Calorimetry (DSC) is a method of thermodynamic analysis based on ...

Schlenk Lines Transfer of Solvents

Source: Hsin-Chun Chiu and Tyler J. Morin, laboratory of Dr. Ian Tonks&#8212;University of Minnesota Twin Cities
Schlenk lines and high vacuum lines are ...

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.

HS-PS1-2.

Chemical Equations

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

Chemical Reactions in Aqueous Solutions

Chemical substances interact in many different ways. Certain chemical reactions exhibit common patterns of reactivity. Due to the vast number of chemical ...

Precipitation Reactions

In a precipitation reaction, aqueous solutions of soluble salts react to give an insoluble ionic compound &#x2013; the precipitate. The reaction occurs ...

Oxidation-Reduction Reactions

Oxidation&ndash;Reduction Reactions

Earth&rsquo;s atmosphere contains about 20% molecular oxygen, O2, a chemically reactive gas that plays an essential ...

Oxidation Numbers

In redox reactions, the transfer of electrons occurs between reacting species. Electron transfer is described by a hypothetical number called the ...

Acids, Bases and Neutralization Reactions

An acid-base reaction is one in which a hydrogen ion, H+, is transferred from one chemical species to another. Such reactions are of central importance to ...

Synthesis and Decomposition Reactions

Synthesis and decomposition are two types of redox reactions. Synthesis means to make something, whereas decomposition means to break something. The ...

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.

HS-PS1-4.

Reaction Rate

The rate of reaction is the change in the amount of a reactant or product per unit time. Reaction rates are therefore determined by measuring the time ...

Measuring Reaction Rates

Polarimetry finds application in chemical kinetics to measure the concentration and reaction kinetics of optically active substances during a chemical ...

Concentration and Rate Law

The rate of a reaction is affected by the concentrations of reactants. Rate laws (differential rate laws) or rate equations are mathematical expressions ...

Apply scientific principles and evidence to explain how the rate of a physical or chemical change is affected when conditions are varied.

Separating Liquids by Boiling Point

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