How To Use a Hotplate With Magnetic Stirrer in 3 Steps

How To Use a Hotplate With Magnetic Stirrer

If you take a chemistry class or work in a laboratory, you likely routinely heat and mix chemicals and reactants. Movies like Spider-Man: Homecoming often portray these tasks as dangerous and imprecise, with characters frantically stirring bubbling flasks and dangling smoking vials over open flames. 

In reality, a hotplate with a magnetic stirrer allows users to easily and safely combine and heat liquid solutions. This versatile tool has three basic components

  • A hotplate, or heatable flat surface, made out of aluminum, ceramic, glass, or steel. This platform uniformly heats flasks and other containers placed on top of it. 
  • A magnet embedded inside the hotplate that you can set to rotate at particular speeds, generating a magnetic field. 
  • A magnetic stirrer bar that spins with the magnet to mix liquids.   

When used properly, a magnetic stirring hotplate can blend solutions more accurately and efficiently than a human stirrer. Because of its functionality, this tool has a broad range of applications in cosmetics and pharmaceutical laboratories, healthcare facilities, schools, scientific research institutes, and other settings. However, an improperly used hotplate can cause serious injury and spoil your solutions. Read on to learn about safe ways to use a magnetic hotplate stirrer and the advantages of adding this instrument to your laboratory. 

A 3-Step Guide to Magnetic Hotplate Stirrers

Laboratories frequently house dangerous chemicals and equipment that require careful handling. A hotplate with a magnetic stirrer is no exception. Luckily, you can safely use this instrument by following three simple steps. 

Insert Small Stir Bar in Flask or Vessel With Stirrable Contents

First, fill a flask or another vessel with the contents that you need to stir. Next, insert an appropriately sized magnetic stir bar into the container.  

Magnetic stir bars come in several shapes, including egg-shaped, octagonal, and polygonal. You can also choose a stir bar with or without a pivot ring. You should select the stir bar that best fits your vessel to ensure safe stirring. For instance, an egg-shaped stir bar will effectively mix solutions in round-bottom flasks. 

Place Flask on Digital Hotplate Containing a Rotating Magnet or Electromagnet

Next, you will carefully place your flask on the digital hotplate stirrer. The tool contains an internal electromagnet or rotating magnet that moves the magnetic stir bar. If your solution will likely bubble or splash when heating, you can attach a safety shield. 

Turn On and Use Speed and Temperature Control Options

Digital hotplates have LCD panels that display temperature and speed. You can use the electronic controls to choose your desired settings. Depending on your needs, you can use the hotplate to heat and stir the flask simultaneously, or you can choose to only heat or stir the solution. 

Once your solution finishes heating and stirring, you can use a magnetic stir bar retriever to remove the stirrer. This tool eliminates the need for you to stick your hand into a potentially harmful solution to fish out the magnetic bar. 

The Advantages of a Combination Hotplate Stirrer

A magnetic hotplate stirrer provides many performance solutions that make it an excellent choice for any laboratory. 

Better and More Precise Temperature Performance

A magnetic stirrer with heating allows for more precise control of temperature than using a gas burner. The average temperature range for hotplates is room temperature to 340°C. Models like the Scilogex SCI550-Pro 7x7 LCD Digital Hotplate Stirrer can reach up to 550°C. 

With a digital hotplate, you can set the exact liquid temperature that you need to heat your solution. Most hotplates have a temperature control accuracy of ±1°C. More sophisticated models like the Scilogex SCI550-Pro have temperature sensors with accuracy of ±0.2°C. 

Optimal Mixing To Save Time Without Sacrificing Accuracy

Say goodbye to painstakingly stirring your solutions by hand. Stirring hotplates enable you to automate your mixing for optimal results. You can input your desired stirring speed, and the hotplate will mix your solution at an accurate and consistent rate. Most hotplates can stir at a maximum rate of 1,000 to 1,500 rotations per minute. 

Some magnetic hotplates allow you to heat and stir multiple flasks simultaneously for maximum efficiency. For example, the Scilogex SCI-S10 10-Place Analog Magnetic Stirrer can accommodate up to 10 flasks at once. The machine provides electronic speed control, which means that the hotplate will keep mixing consistently even as you add or remove flasks.  

Using a stirring magnetic hotplate to heat and mix more than one vessel at the same time streamlines your workflow, saving you time and effort. The tool also eliminates human error, ensuring maximum accuracy. 

Exceptional Safety and a Wide Range of Applications

A magnetic stirring hotplate offers advanced safety features and has a wide range of applications. 

Examples of common protections built into stirring hotplates include: 

  • Excellent chemical resistance 
  • External sensors 
  • A “HOT” warning that appears whenever the instrument reaches 50°C or higher
  • A PID controller that makes sure that the hotplate heats evenly and doesn’t exceed the preset temperature 
  • An optional safety shield to present splashing from heating chemicals 
  • Stir protection 

Of course, even with these built-in features, you should still practice laboratory safety fundamentals at all times when handling a magnetic hotplate. Before using the equipment, you should always perform a quick safety check. To prevent fire or injury, it’s important to ensure that: 

  • The flask is smaller than the hotplate surface 
  • The hotplate is shut off when not in use to prevent burns 
  • The power cord isn’t damaged or frayed 
  • The vessel has no visible cracks or flaws 
  • You are using a heat-resistant vessel, not plastic or thick-walled glassware that may melt or shatter
  • You select the appropriate temperature setting 

A magnetic stirring hotplate also has a wide range of uses, making it a popular piece of laboratory equipment in many settings. For example, you can use this tool for: 

  • Classroom science experiments 
  • Dialysis 
  • Growing bacteria cultures 
  • Oil analysis 
  • PH monitoring 

Upgrade Your Lab by Investing in Digital Hotplates With Magnetic Stirrers

A digital hotplate with a magnetic stirrer is an efficient and highly portable tool. You can use this equipment to quickly heat and stir chemicals for a variety of applications. Thanks to the electronic features, you can feel confident that the instrument will produce quality solutions made to your precise specifications. 

Ready to upgrade your laboratory experience? AmScope offers a variety of magnetic stirring hotplates equipped to handle even the most strenuous applications. Our products provide consistent, reliable performance at reasonable prices. From the classroom to the pharmaceutical laboratory, our hotplate stirrers are the perfect tool to maximize your workflow.