A stir bar, or spin bar, is a small white oblong Teflon-covered magnet. These bars have only one purpose: to stir solutions. They are used in conjunction with a stir motor. You place the stir bar in a container of liquid, then place the container over a stir motor.
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How does a chemistry stir bar work?
Magnetic stirrers use a rotating magnetic field to move a stir bar around in liquid samples. The movement of this stir bar mixes the sample thoroughly with rapid movement and agitation. The speed of the magnetic field is controlled by the user, so it can be customized to the specific sample that’s being stirred.
Why do scientists use magnetic stirrers?
The primary function of magnetic stirrers is to agitate liquids to speed up reactions or enhance mixtures. Magnetic Stirrers are commonly used in chemistry and biology experiments for sample preparation and analysis.
How do I choose a magnetic stir bar?
The Size of the Internal Drive Magnet The size of the magnet inside the stirrer, which may be referred to as the drive magnet, is of great importance when choosing a stir bar size. The length of the bar should be about equal to the magnet size to avoid spinout.
What are the uses of magnetic stirrer with hot plate?
The primary use of magnetic stirrer or hot plate with magnetic stirrer is to conduct biological and chemical experiments by mixing two components. It is equally suitable for solids or liquid samples to obtain a consistent liquid mixture. Examples include media for bacterial growth and chemical synthesis.
How do you use a stirrer?

What is the use of stirrer in a calorimeter?
Stirrer is used in a calorimeter to ensure proper mixing of the contents of the calorimeter. This will help in correct measurement of temperature, and thus the involved heat exchange calculated will have less error.
Who invented magnetic stirrer?
The first magnetic stirrer was patented by Richard Stringham of Utah in 1917. The inventor nicknamed the stir bar a “Flea” because of the way it jumped and spun in the flask.
Can you use a stir bar in a round bottom flask?
elliptical (egg shaped) magnetic stirring bars are particularly well suited for round bottom flasks. Their shape mimics that of a flask and ensures complete mixing.
How do you Stir liquid?

Can magnetic stir bars be autoclaved?
Stir bars are designed to resist harsh chemicals and high temperatures. Therefore, you can autoclave magnetic stir bars.
What are the 2 primary functions of a stirrer hot plate?
A hot plate stirrer or a hot plate magnetic stirrer is a laboratory instrument that is typically used to stir and heat the solution simultaneously. This helps the person performing the experiment speed up the reaction and properly dissolve the solute in the solvent.
How does a magnetic self stirring mug work?
Self Stir Cup is a self-stirring cup that works without batteries. It works with a magnetic pill at the bottom of the cup. This pill automatically spins when it comes into contact with hot drinks. Enjoy well stirred hot drinks without having to stir yourself with a spoon.
What is magnetic stirrer hot plate?
The hotplate stirrer (or hot plate stirrer or hot plate magnetic stirrer) is used for mixing and heating aqueous solutions for a great variety of chemical reactions such as synthesis. VELP hotplate stirrers are available in various models and combinations in both analog and digital configurations.
Why do you stir a reaction?
Stirring allows for the homogenization of mixable liquids and the stir-up of solid particles in liquids. Differences in temperature or concentration are balanced more efficiently during stirring. Additionally, the stirring of liquids speeds up the dissolution process and increases the speed of chemical reactions.
Why is it necessary to stir a reaction while taking the temperature of the reaction?
Stirring and agitating chemical reactions is desirable and stirring reflux systems or any system under heating is necessary to a) distribute the heat evenly throughout the system and b) to prevent splashing and boilovers.
Why should we stir the water before taking the new temperature?
Stirring will help cool a hot drink because it speeds up the process of convection by bringing the hottest liquid at the bottom to the top, where it can be cooled by the air.
What are magnetic stirrers made of?
Many stir bars are made with ceramic or Alnico magnets. Ceramic magnets are inexpensive and common, but not nearly as strong as a neodymium magnet. They have only about 8-10% of the pull force. Alnico magnets are made from aluminum, nickel and cobalt.
How do you remove a stir bar from a flask?
- Go to your nearest giant electromagnet (an NMR or MRI should do the trick)
- Place sample jar near machine.
- Stand well back.
- Turn on magnet, allowing the bar to be gently removed and placed on the floor.
What does stirrer mean?
stirrer. / (หstษหrษ) / noun. a person or thing that stirs. informal a person who deliberately causes trouble.
How do you stir chemicals in a lab?
- Move the bottom of the flask closer to the stir plate.
- Use a bigger stir bar.
- Use a larger or more powerful stir plate (not all plates are created equal).
- If your stir bar gets stuck somehow, pick up the flask and swirl it until the bar is free, or pry it free with a pipette or spatula.
How do you make a magnetic stirrer?

What does a volumetric flask measure?
A volumetric flask is lab glass or plasticware used to prepare a solution. It is used to make up a solution to a known volume. Volumetric flasks are used to measure volumes much more precisely than beakers or Erlenmeyer flasks.
How do you care for a magnetic stirrer?
The magnetic stirrer can be cleaned with either water containing a surfactant detergent additive or isopropanol.
Do magnetic stirrers heat up?
Magnetic stirrers do not include a heating element.