Name: organic lab glassware and safe handling
Uploaded: 2020-03-26T07:22:27.000Z
Duration: 3 min 8 s
Channel: JoVE

K12 Standards

Texas Essential Knowledge and Skills

High School

Chemistry

CHEM.1

CHEM.1.D

Basic Organic Chemistry Techniques

Los procedimientos de laboratorio en química orgánica suelen utilizar equipos y técnicas estándar de cristalería. Los vasos de precipitados y los matraces Erlenmeyer se utilizan a menudo para mezclar y mantener disolventes de forma sencilla. Los matraces de fondo redondo con cuello corto o largo se utilizan para reacciones a altas temperaturas o vacío. Esto se debe a que la forma redonda es más resistente al agrietamiento en estas condiciones.
Las reacciones de calentamiento son un procedimiento común de laboratorio. Sin embargo, un mechero Bunsen no se usa generalmente para compuestos orgánicos porque son inflamables. Al calentar una reacción en un vaso de precipitados o en un matraz Erlenmeyer, normalmente se utiliza una placa calefactora con un agitador magnético. Al calentar una reacción en un matraz de fondo redondo, se utiliza un baño de agua o un manto calefactor para acomodar la forma del matraz.
Muchas reacciones deben calentarse a una cierta temperatura durante un período de tiempo específico. Estas reacciones se realizan bajo reflujo. Una configuración de reflujo utiliza un matraz de fondo redondo que contiene un solvente cuyo punto de ebullición se superpone con la temperatura óptima de la reacción. Se instala un condensador en el matraz y el agua fría entra por el brazo inferior y sale por el brazo superior. A medida que la mezcla se calienta y se agita, el disolvente se evapora y luego se condensa de nuevo en el matraz, preservando el volumen de reacción.
Otra técnica común utilizada en el laboratorio de química orgánica es la filtración, que es un método para separar sólidos de líquidos. La filtración por gravedad es la técnica de filtración más simple utilizada para separar sólidos granulares insolubles. Esta configuración consta de un matraz Erlenmeyer, un embudo cónico y un trozo de papel de filtro doblado. La mezcla se vierte en el embudo y el líquido pasa a través del matraz, llamado filtrado. Los sólidos permanecen en el papel de filtro.
Una técnica de filtración más rápida es la filtración al vacío. Aquí, un embudo de Büchner se conecta a un matraz de filtro mediante un adaptador de goma. El matraz de filtro se parece a un matraz Erlenmeyer, pero tiene un brazo lateral que conecta el matraz al vacío a través de un tubo de vacío. Luego, se coloca un trozo plano de papel de filtro dentro del embudo y se humedece ligeramente antes de encender lentamente la aspiradora. El líquido es aspirado a través del papel de filtro hacia el matraz, mientras que el sólido es retenido en el papel de filtro.
 En este laboratorio, realizará una reacción simple para formar ácido benzoico, lo que le permitirá practicar técnicas simples de química orgánica, como pesar sólidos, medir volumen y realizar filtración al vacío. A continuación, practicarás la técnica de reflejos con tetrahidrofurano.

técnicas básicas de química orgánica

Cristalería en Química Orgánica
Hay piezas estándar de cristalería que se utilizan en el laboratorio de química orgánica. Los vasos de precipitados y los matraces Erlenmeyer se utilizan normalmente para mezclar de forma sencilla o para contener disolventes, pero no deben utilizarse para medir el volumen, a menos que sólo se necesite un volumen aproximado. La cristalería se puede dividir en las siguientes categorías:
<ol>
	<li style="font-size:17px">Cristalería volumétrica - Esto incluye cristalería como cilindros graduados, pipetas de vidrio volumétricas y matraces volumétricos. El propósito de estos artículos es medir o dispensar un volumen preciso de una sustancia. Un cilindro graduado se usa generalmente para medir volúmenes en un laboratorio orgánico. El cilindro graduado tiene una forma cilíndrica larga con marcas de volumen en el lateral. Es esencial utilizar el cilindro graduado más pequeño posible para el volumen necesario con el fin de minimizar el error. Por ejemplo, un cilindro graduado de 25 mL es adecuado para medir 20 mL de reactivo, pero no es preciso para medir un volumen menor, como 5 mL. Sin embargo, no utilice un cilindro graduado de 25 mL para medir 100 mL midiendo cuatro volúmenes de 25 mL; es mejor usar el cilindro graduado de 100 mL.</li>
	<li style="font-size:17px">Contención de reacciones: estas piezas especializadas se pueden utilizar para albergar una reacción química orgánica. Los matraces de fondo redondo son un ejemplo de esta cristalería. A diferencia de los matraces Erlenmeyer, los matraces de fondo redondo proporcionan más superficie y, por lo tanto, proporcionan un calentamiento o enfriamiento más uniforme. Los matraces de fondo redondo se utilizan para realizar reacciones a altas temperaturas o al vacío porque su forma redonda es más resistente al agrietamiento. En esta categoría también se encuentran los cristales especializados conocidos como condensadores, que se utilizan para recoger vapores gaseosos y condensarlos de nuevo en la fase líquida que se va a recoger.</li>
	<li style="font-size:17px">Filtración - Estas piezas de cristalería se utilizan principalmente para ayudar a aislar los precipitados de una mezcla de reacción. Para aislar los precipitados sólidos, se requiere un aparato de filtración. La configuración más simple utiliza un embudo de vidrio conectado a un matraz Erlenmeyer. Dentro del embudo hay un trozo de papel de filtro. La mezcla de reacción que contiene el sólido se vierte en el embudo y la gravedad arrastrará el líquido hacia el matraz, dejando atrás el sólido. Esto se conoce como filtración por gravedad. Sin embargo, esta configuración puede requerir un largo período de tiempo para filtrar el sólido. Una configuración de filtración al vacío sustituye el matraz Erlenmeyer por un matraz de vacío con brazo lateral y el embudo de vidrio por un embudo de filtro de porcelana conocido como embudo Büchner. Este brazo lateral está conectado a una fuente de vacío. Al igual que antes, la mezcla de reacción se vierte en el embudo del filtro y la filtración se ve favorecida por la fuerza del vacío.</li>
	<li style="font-size:17px">Separation – Estos matraces o embudos especializados se utilizan principalmente para extracciones en fase líquido-líquido, que es una técnica que permite la separación de productos mediante el uso de disolventes con diferentes polaridades o hidrofobicidades. Estos líquidos inmiscibles formarán una solución heterogénea que se separa en dos fases. Los embudos separadores tienen una válvula conocida como llave de paso en la parte inferior, que permite la separación de las fases vertiéndolas en un nuevo recipiente.</li>
	<li style="font-size:17px">Transport – Esta cristalería consiste principalmente en botellas o viales con una tapa correspondiente. Esta cristalería se utiliza principalmente para transportar materiales potencialmente peligrosos de forma segura.</li>
	<li style="font-size:17px">Uso general - Esta categoría se compone de cristalería como vasos de precipitados, matraces Erlenmeyer, varillas de vidrio y cualquier otra pieza miscelánea.</li>
</ol>
Pesaje de reactivos orgánicos
Los reactivos orgánicos pueden venir en múltiples formas, y es importante practicar una buena técnica de laboratorio al obtener estos reactivos para su uso en experimentos. Revise siempre la MSDS de un reactivo para determinar los peligros potenciales cuando trabaje con él. Los reactivos sólidos deben medirse utilizando botes de pesaje o papel de pesaje y el tipo de balanza adecuado.
Si se requiere una medición precisa, utilice una balanza analítica. Si se va a utilizar una gran cantidad de reactivo, utilice una balanza de carga superior. Coloque un bote de pesaje o papel de pesaje en la balanza y presione el botón de "tara". La función de tara anulará la masa del papel de pesaje. Utilice siempre espátulas para transferir los reactivos sólidos desde el suministro hasta el recipiente de pesaje. Nunca vuelva a utilizar la misma espátula para diferentes reactivos, ya que esto puede contaminar los reactivos originales. Y nunca devuelva el exceso de reactivo a la botella de stock. En su lugar, deséchelo de la manera apropiada según las instrucciones.
Al transferir el sólido al recipiente apropiado, use un pequeño embudo para verter con cuidado el sólido en el interior. Si queda algún sólido, utilice una pequeña cantidad del disolvente que se utilizará en el recipiente de pesaje y transfiéralo al matraz.
Los líquidos orgánicos se pueden medir mediante el uso de cristalería volumétrica, como un cilindro graduado. Calcule el volumen del líquido usando su densidad, luego tara el matraz de reacción en la balanza. Utilice una pipeta o un cilindro graduado para transferir el volumen directamente al matraz de reacción. Siga las pautas para el tipo específico de cristalería. Nunca reutilice la misma pieza de cristalería para varios reactivos y nunca devuelva el exceso de reactivo a las botellas de caldo líquido. En el caso de los líquidos, c
Calentamiento de reacciones orgánicas
A veces se requiere calor para permitir que ocurra una reacción química orgánica. En el entorno general del laboratorio, el calor se aplica comúnmente utilizando un quemador Bunsen con una llama de gas directa. En los laboratorios de química orgánica, una llama abierta de un mechero Bunsen puede crear una situación peligrosa. Los reactivos orgánicos, en particular los disolventes, son altamente combustibles y algunos forman vapores con relativa facilidad. Por esa razón, los quemadores Bunsen no se utilizan en los laboratorios de química orgánica.
En su lugar, se utilizan baños de calentamiento, placas calefactoras o mantos para proporcionar una fuente indirecta de calor. Las placas calefactoras con función de agitación magnética se utilizan para calentar vasos de precipitados y matraces Erlenmeyer. Las mantas calefactoras están diseñadas para calentar de forma segura un matraz de fondo redondo con diferentes volúmenes. Los baños de agua se utilizan cuando la temperatura de la reacción no necesita superar los 100 °C. Una reacción en la cristalería se sumerge en un baño de agua que se calienta con una placa caliente. La temperatura se modula al rango adecuado. Si la temperatura requerida debe superar los 100 °C pero no los 250 °C, se puede utilizar un manto de silicona. Si la temperatura debe superar los 250 °C, se puede utilizar un baño de arena.
Muchas reacciones requieren ser calentadas a una cierta temperatura durante largos períodos de tiempo para que continúe. Sin embargo, si una reacción se calienta durante un largo período de tiempo, el solvente puede evaporarse, causando una pérdida de la solución de reacción. En su lugar, a menudo se utiliza una configuración de reflujo, que utiliza un matraz de fondo redondo que contiene un solvente. El punto de ebullición del disolvente se superpone con la temperatura óptima de la reacción. El matraz de fondo redondo se sujeta a un soporte y se instala un condensador en el matraz. El agua fría fluye a través del condensador desde el brazo inferior hasta el brazo superior mientras la mezcla se calienta y agita. A medida que se calienta la mezcla, el disolvente se evapora y luego se condensa de nuevo en el matraz, preservando el volumen de reacción.

Técnicas Básicas de Química Orgánica

Cristalería en Química Orgánica
Hay piezas estándar de cristalería que se utilizan en el laboratorio de química orgánica. Los vasos de precipitados y los matraces Erlenmeyer son ...

Education

Educación

JoVE Lab Manual

Química

organic lab glassware and safe handling

Organic chemistry labs use specific glassware, careful weighing steps, and controlled heating to keep reactions safe and accurate. Beakers and Erlenmeyer flasks are often used for mixing or holding solvents, but they are not meant for measuring volume unless only an approximate amount is needed.

Volumetric glassware is used when a precise volume matters. This group includes graduated cylinders, volumetric pipettes, and volumetric flasks. A graduated cylinder is commonly used in the organic lab because it has volume markings along a long cylinder. It is best to choose the smallest cylinder that can measure the needed amount. For example, a 25-mL graduated cylinder can measure 20 mL, but it is not accurate for a small volume like 5 mL. It is also better to use a 100-mL graduated cylinder for 100 mL than to measure four separate 25-mL portions.

Other glassware is built to hold reactions or help them proceed under specific conditions. Round-bottom flasks provide more surface area than Erlenmeyer flasks and allow more even heating or cooling. They are useful for reactions under high heat or vacuum because their round shape is less likely to crack. Condensers are another important type of glassware. They collect vapor and turn it back into liquid so it can be collected again.

Glassware is also used for filtration, separation, transport, and general lab work. To remove solid precipitates, a simple gravity filtration setup uses a glass funnel, filter paper, and an Erlenmeyer flask. The liquid passes through while the solid stays behind, but the process can take a long time. A vacuum filtration setup is faster and uses a vacuum flask with a side arm, a B&amp;uuml;chner funnel, and a vacuum source. For liquid-liquid phase extractions, separatory funnels are used to split immiscible liquids into two layers. These flasks and funnels separate products by using solvents with different polarities or hydrophobicities. The stopcock at the bottom lets the layers be drained into a new container. Bottles and vials with matching caps are used for safe transport of hazardous material. Beakers, Erlenmeyer flasks, glass rods, and other mixed-purpose items fall into the general use category.

Organic reagents also need careful handling during weighing and transfer. Students should always check the reagent MSDS, or material safety data sheet, for hazards first. Solid reagents are measured on weighing boats or weighing paper with the correct balance. Use an analytical balance for precise mass and a top-loading balance for larger amounts. After placing the weighing boat on the balance, press tare to zero out its mass. Transfer solids with spatulas, but never use the same spatula for different reagents. Do not return extra reagent to the stock bottle. Instead, discard it as instructed. A small funnel can help move the solid into the reaction vessel, and any residue on the boat can be rinsed in with a small amount of the solvent being used.

Liquids are measured with volumetric glassware such as a graduated cylinder. Their volume can be calculated from density, and the reaction flask can be tared on the balance before transfer. A pipet or graduated cylinder is then used to add the liquid directly to the flask. The same piece of glassware should not be reused for multiple reagents, and excess liquid should never go back into the stock bottle. When heat is needed for an organic reaction, a Bunsen burner is avoided because organic solvents and vapors can ignite easily. Instead, labs use hotplates, heating baths, or heating mantles. Hotplates with magnetic stirring heat beakers and Erlenmeyer flasks. Heating mantles are made for round-bottom flasks. Water baths are used when the reaction temperature stays below 100 &amp;deg;C. Silicone mantles are used when the temperature must be above 100 &amp;deg;C but below 250 &amp;deg;C, and sand baths are used above 250 &amp;deg;C. For long heating times, a reflux setup helps prevent solvent loss. A round-bottom flask with solvent is clamped to a stand, a condenser is attached, and cold water flows from the bottom arm to the top arm while the mixture is heated and stirred. The solvent vapor condenses and returns to the flask, which keeps the reaction volume steady.

Organic Lab Glassware and Safe Handling

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Balancing Equations and Reactant Limits

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Oxidation States in Redox Reactions

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Gas Laws Behind the Ideal Gas Equation

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acid and base concentrations

Acids, Bases, and pH in Titration

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Buffer pH and the Common Ion Effect

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Solubility in Water and Other Solvents

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Flame Test Metal Color Clues

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Hydrogen Emission Lines

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Absorbance Spectra and Beer-Lambert Analysis

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Reaction Order and Rate Constants

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Reaction Rate, Arrhenius, and Catalysts

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Battery Power from Redox Reactions

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Electroplating with Electrolytic Cells

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Recording a Reproducible Lab Experiment

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basic organic chemistry techniques

Organic chemistry labs use specific glassware, careful weighing steps, and controlled heating to keep reactions safe and accurate. Beakers and Erlenmeyer flasks are often used for mixing or holding solvents, but they are not meant for measuring volume unless only an approximate amount is needed. Volumetric glassware is used when a precise volume matters. This group includes graduated cylinders, volumetric pipettes, and volumetric flasks. A graduated cylinder is commonly used in the organic lab...

melting points

How Impurities Change Melting Points

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Boiling Point and Vapor Pressure

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recrystallization

Purifying Crystals by Solubility

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extraction

Separating Mixtures with Solvent Extraction

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simple distillation

Separating Liquids by Boiling Point

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steam distillation

Steam Distillation and Low-Boiling Separation

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thin-layer chromatography

TLC Separation by Polarity

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Separating Mixtures by Polarity

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uv-vis spectroscopy of dyes

How Dyes Absorb Visible Light

Dyes absorb visible light because their molecular structure lets them interact with specific wavelengths. When light hits a substance, some light is absorbed and the rest is reflected or transmitted. The color we see depends on the wavelength that is reflected. A blue substance reflects blue light, around 430 to 480 nm, and absorbs the complementary orange region, around 590 to 630 nm. Compounds that do not absorb in the visible range appear colorless to the human eye. Light also has energy and...

identifying alcohols

Alcohol Tests for Primary, Secondary, and Tertiary

Alcohol tests can help sort alcohols by structure and reactivity. Alcohols are organic molecules with a hydroxyl group attached to an alkyl or aryl group, written as ROH. If the carbon with the hydroxyl group has one R group, the alcohol is primary. If it has two R groups, it is secondary. If it has three R groups, it is tertiary. Alcohols can also be aromatic when they contain a benzene ring. Phenol is the simplest aromatic alcohol. To identify an alcohol, chemists can use its chemical...

chemistry

Videos completos y enfocados en el plan de estudios, tanto para los instructores como para los estudiantes de los cursos de laboratorio de introducción a la química.

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Learn how high school organic chemistry labs use glassware, filtration, separatory funnels, weighing tools, and safe heating methods for reactions.

Organic Lab Glassware and Safe Handling | JoVE K12

Prepárese para enseñar Técnicas Básicas de Química Orgánica con esta guía para instructores de 3 minutos. Cubre los pasos clave de preparación para el laboratorio Chemistry en JoVE Lab Manual.

Preparación del instructor para Técnicas Básicas de Química Orgánica en Chemistry - Más de 4.4K visualizaciones | JoVE Lab Manual

Siga los procedimientos paso a paso de Técnicas Básicas de Química Orgánica en este video de protocolo estudiantil de 16 minutos. Parte de la colección Chemistry en JoVE Lab Manual.

Protocolo estudiantil de Técnicas Básicas de Química Orgánica en Chemistry - Más de 30K visualizaciones | JoVE Lab Manual

Scientific Laws and Theories

Scientific Laws

In science, a law is defined as a concise, verbal or mathematical, statement that summarizes a vast number of experimental observations. ...

The Scientific Method

Chemistry is an empirical science. Scientists often pose questions to understand the chemistry in everyday life and seek answers to these questions. To ...

CHEM.1.A

What is an Experiment?

An experiment is a planned activity carried out under controlled conditions. The purpose of an experiment is to investigate the relationship between two ...

Study Design in Statistics

A study design is a set of techniques that allow a researcher to collect and analyze data from different variables defined for a specific research ...

Observational Studies

Observational studies are a type of analytical study where researchers observe events without any interventions. In other words, the researcher does not ...

Experimental Designs

An experimental design is a systematic process that allows researchers to evaluate the relationship between dependent and independent variables. There are ...

Randomized Experiments

The randomization process involves assigning study participants randomly to experimental or control groups based on their probability of being equally ...

Crossover Experiments

Crossover experiments, also called the repeated-measurements design, is a study design in which all experimental units are exposed to all treatments in ...

Controls in Experiments

When conducting an experiment, it is crucial to have control to reduce bias and accurately measure the dependent variables. It also marks the results more ...

Bias

Bias refers to any tendency that prevents a question from being considered unprejudiced. In research, bias occurs when one outcome or answer is selected ...

Blinding

Blinding is a commonly used method of not telling participants which treatment a subject is receiving. Blinding is a critical part of a randomized control ...

CHEM.1.B

Proper Personal Protective Equipment

Robert M. Rioux &#38; William A Elliott, Pennsylvania State University, University Park, PA
Hazards are many and varied in the laboratory, but the right ...

Emergency Eyewash and Shower Stations

Robert M. Rioux, Pennsylvania State University, University Park, PA
The Occupational Safety and Health Administration (OSHA) mandates that an emergency ...

Electrical Safety

Robert M. Rioux &amp; Suprita Jharimune, Pennsylvania State University, University Park, PA
Among the many hazards present in the laboratory, electrical ...

Working with Centrifuges

Source: Robert M. Rioux &amp; Suprita Jharimune, Pennsylvania State University, University Park, PA
Earth's gravitational force is capable of separating ...

Working with Hot and Cold Sources

Source: Robert M. Rioux &amp; Suprita Jharimune, Pennsylvania State University, University Park, PA
Working with extreme temperatures, both high and low, ...

guidelines-in-case-of-a-laboratory-emergency

Guidelines in Case of a Laboratory Emergency

Robert M. Rioux &amp; Zhifeng Chen, Pennsylvania State University, University Park, PA
The most common laboratory emergencies include chemical spills, ...

chemical-storage-categories-hazards-and-compatibilities

Chemical Storage: Categories, Hazards And Compatibilities

Source: Robert M. Rioux &amp; Taslima A. Zaman, Pennsylvania State University, University Park, PA
While the use of various chemicals in experimental ...

Safe Handling of Mineral Acids

Source: Robert M. Rioux &#38; Taslima A. Zaman, Pennsylvania State University, University Park, PA
A mineral acid (or inorganic acid) is defined as a ...

Handling Chemical Spills

Source: Robert M. Rioux &#38; Taslima Zaman, Pennsylvania State University, University Park, PA
Since chemicals are commonly used for laboratory research ...

Proper Use of Autoclaves

Robert M. Rioux &amp; Zhifeng Chen, Pennsylvania State University, University Park, PA
Autoclaving is one of the most commonly used methods in the ...

Fume Hoods and Laminar Flow Cabinets

Robert M. Rioux &amp; William A. Elliott, Pennsylvania State University, University Park, PA
Fume hoods and laminar flow cabinets are engineering controls ...

handling-air-and-water-sensitive-chemicals-using-a-schlenk-line

Handling Air- and Water-Sensitive Chemicals Using a Schlenk Line

Robert M Rioux, Ajay Sathe, Zhifeng Chen, Pennsylvania State University, University Park, PA
The use of reagents sensitive to oxidation or moisture ...

proper-operation-of-vacuum-based-equipment

Proper Operation of Vacuum Based Equipment

Source: Robert M. Rioux, Ajay Sathe &#38; Zhifeng Chen, Pennsylvania State University, University Park, PA
Vacuum is required for a number of laboratory ...

Operating the Glovebox

Robert M Rioux, Ajay Sathe, Zhifeng Chen, Pennsylvania State University, University Park, PA 
A glovebox is an isolated enclosure that is designed to ...

operation-of-high-pressure-reactor-vessels

Operation of High-pressure Reactor Vessels

Robert M Rioux, Pennsylvania State University, University Park, PA
The use of gases in a synthetic chemistry laboratory is essential for carrying out a ...

CHEM.1.C

Lab Techniques

Measurement Accuracy
The ability to repeat an experiment and get the same results, or reproducibility, is essential in scientific research. However, ...

Scientific Measurement and Lab Skills

Two-Dimensional Graphs
Some chemistry experiments take the form of directly changing one property of the system that you are studying otherwise known as ...

Proper Lab Notebook Keeping

Organic Lab Notebook Keeping
Record keeping is a vital skill in science and organic chemistry labs. Without proper notes, descriptions, quantities, or ...

Glassware in Organic Chemistry
There are standard pieces of glassware that are used in the organic chemistry lab. Beakers and Erlenmeyer flasks are ...

Measurement: Standard Units

Every measurement provides three kinds of information: the size or magnitude of the measurement (a number), a standard of comparison for the measurement ...

Measurement: Derived Units

The International System of Units or SI system, by international agreement, has fixed measurement units for seven fundamental properties: length, mass, ...

uncertainty-in-measurement-accuracy-and-precision

Uncertainty in Measurement: Accuracy and Precision

Scientists typically make repeated measurements of a quantity to ensure the quality of their findings and to evaluate both the precision and the accuracy ...

uncertainty-in-measurement-reading-instruments

Uncertainty in Measurement: Reading Instruments

Counting is the type of measurement that is free from uncertainty, provided the number of objects being counted does not change during the process. Such ...

CHEM.1.E

Scientific and engineering practices. The student, for at least 40% of instructional time, asks questions, identifies problems, and plans and safely conducts classroom, laboratory, and field investigations to answer questions, explain phenomena, or design solutions using appropriate tools and models. The student is expected to:

Organic Lab Glassware and Safe Handling

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