Using Poinsettia Leaves as an Acid / Base pH Indicator

Click image to view this resource in my TpT store.

I LOVE this fun holiday activity!

We science teachers know that many plants contain pigments that can be used as pH indicators.  I think we have all created a stink in our homes or labs by boiling red cabbage to use the "juice" as an acid/base indicator!



Did you know that you can do the same with the pigments found in red Poinsettia leaves?

These plants contain anthocyanins, which are water soluble pigments.  These pigments are responsible for the the red, purple, and blue colors seen in flowers, fruits, and vegetables. Anthocyanins respond to changes in pH.  I absolutely love lab activities that use items like this in the lab.  My students are often surprised and excited to discover that household items, such as the Poinsettia or red cabbage, can be used for scientific purposes.  Using the Poinsettia leaves as an acid/base indicator makes for a super fun lab activity around the holidays.

In this lab, the students will use a pigment solution extracted from the leaves of the poinsettia to establish a known pH baseline.  Students will then use this baseline to predict the pH of common household items.

The images below will give you a great idea of all that is involved with this lab. Click on any image below to view this resource in my TpT store.

I hope you find this useful in your science classes.  Enjoy the holiday season!

Lab Safety Tip: What You Need to Know About the Eyewash Fountain and the Lab Safety Shower

👉👉 Required Reading for the Week:

Scientific American - Danger in School Labs: Accidents Haunt Experimental Science

When was the last time you tested your eye wash fountain and your lab safety shower? Did you know that they are supposed to be flushed once a week according to ANSI standards? I think it is safe to say that the plumbed emergency equipment in our science labs is often neglected. We walk past the eyewash and the shower day after day after day, but rarely stop to inspect it. Since I have never had to pull the handle (thankfully!) on either piece of equipment in an emergency, I rarely stop to think about the routine maintenance that is required.

But I am not an expert. And while I hope this blog post puts a nagging reminder in your brain, use the links in this post to read what the experts have to say. My go-to source of lab safety information is Flinn Scientific. Read this article about the eyewash and safety shower.

Here are the basics about the lab eyewash fountain:

• The eyewash must provide a flow of water to both eyes simultaneously.
• The affected area must be irrigated for a minimum of 15 minutes.
• Keep both eyes open and rotate eyeballs in all directions.
• Regulation of volume and pressure is required to maintain a soft flow of water to the eyes.
• Location of the eyewash is important.  Travel time from a work station to the eyewash should be within 10 seconds.
• Water temperature should be "tepid" which means lukewarm. Acceptable temperature range is 78 - 92 degrees Fahrenheit.
• Weekly testing should occur to verify flow. This also clears the water line to remove dirt from the pipes.

Here are the basics about the lab safety shower:

• The shower should provide a deluge large enough to encompass the whole body.
• Remove contaminated clothing. Every second counts. Don't be modest. It will only slow you down. Remove contaminated clothing!
• The shower should deliver a pattern of water that is 20 inches across.
• Water flow should be 20 gallons per minutes at a velocity low enough to not injure the user.
• The plumbed safety equipment should be clearly marked with signs and by painting the walls and floor surrounding the equipment a bright color.

For us middle or high school teachers, words cannot begin to describe how busy we are during the school day. If your safety equipment does not meet the standards, it is time to have a talk with your school administrator. The safety of your students depends on it!

And please don't forget to take the time to inspect the equipment. No eye wash fountain should ever look like this!

Looking for a place to start in developing your lab safety unit?  These resources are posted in my TpT store:

Lab Safety Chat

Lab Safety Bundle

Lab Safety PowerPoint

Lab Safety Color by Number

Lab Safety Digital Hidden Picture Activity

Good lab safety instruction is essential in providing safe lab experiences for our students.  Good luck!

Lab Safety Tip of the Week #4

Safety Tip #4:

Wear Your Safety Goggles

Required Reading for the Week:  "Wear Your Safety Goggles."  Click red text to view this article.

Accidents happen so quickly. And hindsight is a wonderful thing. In the above article, a science teacher has permanent damage to the eye after conducting a demonstration with no eye protection. And a college student goes in late to their organic chemistry lab, and joins a group of two other students at the fume hood. An explosion occurs in the hood. The student was present in the lab less than two minutes and now has permanent eye damage. It seems so simple after the fact ... Why didn't you have on your safety goggles?

WHERE ARE YOUR
SAFETY GOGGLES!!!!!

As a science teacher, I have to plead guilty. I have often prepped a lab for my students without wearing goggles. But when my students are engaged in lab activities, I am a stickler for the rules. We wear the goggles. Always. No questions asked. But it is always a battle. Students do not like to wear safety goggles, and I am constantly having to tell students to put their goggles back on. Unfortunately, most of us are having to carry 30 (and sometimes more!) students into the lab. As soon as you tell one student to put their goggles back on, another student across the room has taken theirs off! Sound familiar?

You, as the instructor, have to be persistent and consistent. Establish the rule of wearing safety goggles. Do not deviate from this rule (EVER!), and have consequences for those who do not obey the rules. Have a conversation with your school administration about lab safety to establish a plan of action for those students who fail to follow the rules. You want to make sure that you have "back up" from admin in case consequences to the student need to be doled out.

Let's move away from student behavior, and on to the goggles themselves. What kind should you use? Are all goggles the same?

All goggles are not the same! And even though many types of goggles might meet regulations and guidelines and be approved for our school labs, some of them are not the best choices for our students. In my opinion, eye protection should have a complete and snug fit around the eye, and be held to the face by a strap that goes around the back of the head. Yes, the students hate these types of goggles, but it is a battle worth fighting.  Here is an excellent article from Flinn Scientific about regulations and standards of safety goggles.

Next topic:  The storage and sanitation of goggles.  I took this picture a few years ago while visiting in a neighboring high school. If you are going to use one classroom set of goggles, and students will be sharing goggles with other students, please take great care in the sanitation of goggles. This picture shows a great goggles sterilizer, but it was not being used correctly. Goggles were not placed in individual slots. They were haphazardly thrown in the cabinet. The inside of the sterilizer was dirty, and it was obvious the goggles had never been washed. Here is an excellent video on the use of the goggles sterilizer. If at all possible, I highly recommend that each student have their own pair of goggles that are not shared with another student.

In summary, 

• Students must wear goggles and this is not negotiable!
• Make sure you purchase eye protection that meets the safety standards.
• Practice what you preach!  The instructor needs to be be the role model in laboratory safety.

Looking for a place to start?  These resources are posted in my TpT store:

Lab Safety Chat

Lab Safety Bundle

Lab Safety PowerPoint

Lab Safety Color by Number

Lab Safety Digital Hidden Picture Activity

Good lab safety instruction is essential in providing safe lab experiences for our students.  Good luck!

Lab Safety Tip of the Week #3:

Tip #3:

Be Ready for the Students to Return to Class!

Required reading for this week:  Worst Lab Accidents in History:  Labs are Dangerous!

In today's lab safety tip of the week, I wanted to present some statistics about accidents in school labs.  After doing some internet searching I have come to realize that there is very little in the way of statistics about school lab accidents.  You can find lots of articles about individual accidents, but there is not any cumulative data that I could find.  How many kids get hurt each year?  How many are burned by heat?  How many suffer from chemical  burns?  I wonder how shocked we would be if we had the answers to these questions.

Many students have already returned to classrooms across the country, and the rest will soon follow as Labor Day approaches.  So the focus of the tip of the week is ... Are you ready for the students to return to class?  I am not referring to such things as having enough desks in your room, or getting paper from the supply room.  What I mean is:  Do you have your lab safety plan in place and ready to roll out when students enter your room?

Here is a checklist of things to consider and to have ready when students return to your class:

• Lab has been inspected.  You have checked all water faucets, electrical outlets and gas jets.  Work orders have been submitted for any faulty items.
• You have cleaned and tested the eyewash fountain.
• You have tested the safety shower.
  
• Fire blanket is accessible.
• Fire extinguisher has been inspected.
• You have enough goggles for each student.  
• YOU HAVE CLEANED THE GOGGLES!
• Lab aprons are clean and readily available. 
• Lab tables are clean and each lab station is stocked with basic items.  
• Sinks are clean and drain properly. 
• Chemicals are properly stored and locked in a chemical storeroom.
• Any unlabeled chemicals should be discarded from the chemical storeroom.
• Fume hood has been inspected to insure that it draws properly.
• Glassware has been inspected.  Chipped and broken pieces have been discarded.
• Exits from the lab are properly marked and unblocked.
• Lab safety rules are posted in the classroom and in the lab area.
• Have a handout of lab safety rules, and make enough copies for each student.
• Have a lab safety contract and have each student and their parents sign it.  Keep on file all year long.
• Have a medical emergency form for each student.  Be aware of the allergies or other medical conditions of your students.
• Lecture on lab safety at the start of the year.
• Prepare a quiz or test on lab safety.  Require each student to score 100% before allowing them in the lab.
• Have MSDS (Material Safety Data Sheets) for each chemical you plan on using in a lab activity.
• Talk to your administrator about how a crisis will be handled.  How will you summon help in an emergency?

Whew! There is a lot to do to get ready for our students to return to class!  To sum it up, the lab safety tip of the week is:  Be proactive, be prepared and be ready when the students return.

Have a great school year!

The Ultimate Lab Safety Bundle for Teachers

Lab Safety Tip of the Week #2

Tip #2:  

Make Use of Online Resources

Required reading for this week:
8 Violations for School in Wake of Lab Fire

Science teachers simply cannot receive enough training in laboratory safety.  For the first year science teacher, training in laboratory safety is a MUST!  But what about the veteran teachers?  After teaching for 30+ years, do I still need to receive training in laboratory safety?  The answer to that is an emphatic YES!!

Teachers are often asked to plan their own professional development.  In my school district, science teachers from all schools in the district meet as a group before students start school.  After school is in session, the science department within my school has monthly meetings.  I feel sure that this type of professional development occurs in other districts as well.  One priority of these annual or monthly meeting should be refresher courses in laboratory safety.

There are many, many online resources available to science teachers in laboratory safety training. And most of them are FREE.  At every single inservice held at the start of the school year, safety training should be required.  Check out the free lab safety videos from Flinn Scientific. Flinn offers 9 courses in laboratory safety, and each of them is free.  In this video, you can get an overview of all the safety training made available by Flinn,  Take advantage of this amazing resource!  Show one or more of these safety videos in your science department meetings.  (Please note that while I am a big fan of Flinn Scientific, I am in no way connected with this company.)  You can also find very comprehensive (and free) materials at Carolina Biological.

In reading about laboratory safety for this post, it seems that most accidents are occurring in the labs of veteran teachers.  I think arrogance, complacency, and "letting down your guard" are probably to blame.  This is the reason veteran teachers need continuing education in lab safety.  Will a veteran teacher learn anything new from such training?  Maybe not.  But it brings the issue of lab safety to the forefront of our thinking.  We need to be reminded, and often!

To sum it up, the lab safety tip of the week is:  Make Use of Free Online Resources to offer continuing lab safety training for the teachers in your department.

Links to other resources include:

The Lab Safety Institute
Environmental Health and Toxicology
Lab Safety Guidelines
OSHA Guidelines on Lab Safety

Lab Safety Tip of the Week #1

Lab Safety:

Make It A Priority!

Another school year is about to begin. Do you have a lab safety instruction unit ready to use with your science students?

Every year at this time, science teachers must review how they are going to address lab safety with biology and chemistry students. Lessons and materials used with students need to be updated. Solid lab instruction will help ensure that another school year will pass and your lab will remain accident free.

Our science students absolutely need GREAT lab experiences. They need to use chemicals, Bunsen burners, hot plates, and glassware. To do less would be depriving them of a good science education. If you make laboratory safety a top priority with the students, they will respond. When they see you being safe and stressing safety at the beginning of each lab, they will behave appropriately. And if they don't, drastic measures will have to be taken before that student can enter the lab again.

One goal that I set for my blog, is to post a "Lab Safety Tip of the Week." To prepare for this series of blog posts, I did some online searching into lab accidents.  I was looking for up to date statistics about safety in middle and high school labs. While I haven't yet found the stats I am looking for, I did come across this video. It is posted by CSB: US Chemical Safety Board. The video is called, "After the Rainbow."  Without reading another word of this blog post, take 5 minutes to watch this video.

Did you watch it?  If that doesn't make you stop and consider your lab safety instruction, nothing will.

Back to the Lab Safety Tip of the Week.  Here is my first lab safety tip.

Before students walk in the door, have a plan.  The first few days of your class must include the following:

• Students must get written copies of your lab safety rules.
• You must go over each and every rule.
• Take the students to the lab and point out all of the lab safety features:  Eyewash, safety shower, fire extinguisher, fire blanket, etc.
• Students must sign a lab safety contract.  Parents must sign it too!
• Students and parents must fill out a medical emergency form.
• Students must take and pass a lab safety quiz.

Make sure that you know what you are going to do in case of an emergency. Talk to your school admin to make sure that all parties agree on a plan of action.  

Lab Safety Tip of the Week #1:  Develop and implement a lab safety plan.

Looking for a place to start?  These resources are posted in my TpT store:

Lab Safety Chat

Lab Safety Bundle

Lab Safety PowerPoint

Lab Safety Color by Number

Lab Safety Digital Hidden Picture Activity

Good lab safety instruction is essential in providing safe lab experiences for our students.  Good luck!

It's February ... And That Means Daphnia Love is in the Air!

This post has been updated.

Click here to view the updated Daphnia heart rate lab.

Onion Root Tip Mitosis Squash Preparation Protocol (Step by Step Chromosome Squash Method)

This post outlines a step by step onion root tip mitosis squash preparation protocol for biology teachers looking to prepare chromosome squash slides.

When you can smell the onions at the end of my hallway, you know it is time to study cell division and make chromosome squash slides. Even after more than 30 years of teaching, this remains one of my favorite biology labs. Students experience everything from frustration when a slide does not turn out to real excitement when they peer into the microscope and realize they made a good one.

What exactly is a chromosome squash?  

A chromosome squash is a slide preparation technique that uses actively dividing cells from an onion root tip to show the different phases of mitosis under a microscope.

How long is this lab?  

This lab takes several days to complete. A short amount of class time is needed to start the onion roots growing. After about five days, students cut the root tips. You should then allow at least two additional class periods for slide preparation and microscopy.

Are there safety precautions that should be followed?  

Yes. This lab requires the use of concentrated hydrochloric acid. It should be conducted in a well ventilated lab with access to a fume hood and an eye wash station. Students must wear safety goggles and lab aprons at all times.

Onion Root Tip Mitosis Squash Preparation Protocol

Begin by purchasing onion sets from a local feed and seed store or a biological supply company. For variety, I typically use red, yellow, and white onions. The color of the onion does not affect the outcome of the lab, but students enjoy growing them, and the lab tables look great when they are full of sprouting onions.

The next step is to "plant" the onions. As you can see in the photo, you will need small plastic cups and toothpicks. A 50-mL beaker works well, also. Students insert three toothpicks into each onion to form a tripod and suspend the onion over a cup filled with water. This setup takes about 20 minutes of class time. Root tips are typically ready for use after about five days.

The root tip is a region of rapid cell division. As the root grows, cells divide continuously, making this tissue ideal for observing mitosis. Once the root tips reach a length of approximately one inch, use a razor blade to cut the roots away from the bulb. Place the root tips in 70 percent isopropyl alcohol. The alcohol kills and preserves the cells, and because many cells are actively dividing, they are often arrested in one of the phases of mitosis. The root tips must soak in the alcohol for at least 24 hours before slide preparation.

Day 5:  Roots are long enough to be cut.

Ready to make the slide?  

It is important to forewarn students that this procedure is not perfect. Several attempts may be required before a slide is clear enough to observe the phases of mitosis. This trial and error is part of the learning process and helps students develop patience and laboratory skills.

To begin slide preparation, remove a root tip from the isopropyl alcohol and place it in a solution of hydrochloric acid and ethyl alcohol. After the appropriate amount of time, transfer the root tip to Carnoy’s solution. Next, place the root tip on a microscope slide and cover it with aceto-orcein stain. While the tissue is in the stain, students should finely chop the root tip using a razor blade. For best results, thorough chopping helps separate the cells.

The final step is the squash technique. Place a cover slip over the chopped root tip and apply gentle, even pressure with your thumb. This spreads the cells into a thin layer suitable for viewing under the microscope.

Place the prepared slide under the microscope and examine it for cells in the different stages of mitosis. Because this technique can be challenging, multiple attempts may be necessary before a clear slide is obtained.

When students finally observe a successful slide, the excitement in the lab is immediate and contagious. I encourage students to take photographs of their slides using their cell phones. While I have never quite mastered this skill myself, students are surprisingly good at capturing clear images.

Have fun teaching!

Frequently Asked Questions: Onion Root Tip Mitosis Squash Preparation

What is an onion root tip mitosis squash?
An onion root tip mitosis squash is a slide preparation technique that uses actively dividing cells from onion root tips to observe the phases of mitosis under a microscope.

What materials are needed for an onion root tip chromosome squash?
This lab requires onion bulbs, water, small cups or beakers, toothpicks, razor blades, microscope slides and cover slips, 70 percent isopropyl alcohol, hydrochloric acid, ethyl alcohol, Carnoy’s solution, and aceto orcein stain.

What stain is used for onion root tip mitosis squashes?
Onion root tip mitosis squashes are commonly stained with aceto orcein or acetocarmine to make chromosomes visible during the stages of mitosis.

What are the steps in the onion root tip mitosis squash preparation protocol?
The procedure includes growing onion roots, cutting and preserving the root tips, treating the tissue with acid and alcohol solutions, staining the cells, chopping the root tip, and gently squashing the tissue under a cover slip to spread the cells.

Why are my chromosome squashes unclear or difficult to see?
Common issues include insufficient chopping of the root tip, too much or too little pressure during the squash, overstaining or understaining, or using root tips that are not actively dividing.

Percent Composition Lab: Chemistry Experiment Using Baking Soda

Percent Composition Lab: Chemistry Experiment Using Baking Soda

Percent composition labs help chemistry students understand how the mass of elements relates to the total mass of a compound. In this hands-on percent composition lab, students determine the percent composition of carbon in sodium bicarbonate by reacting baking soda with sulfuric acid and measuring the carbon dioxide released.

This percent composition chemistry experiment allows students to calculate percent composition experimentally, compare their results to the theoretical value, and determine percent error. It is ideal for high school chemistry students learning percent composition, mass percent, and stoichiometry.

For the extremely busy chemistry teacher, it doesn't get much better than this for a great chemistry lab.

Imagine this:

✔ Quick setup
✔ No crazy materials
✔ Hands-on science
✔ And your students actually having fun while learning percent composition

Sounds like a dream? Nope — it's just good teaching! 😎✨

TL;DR? Find this lab in my TPT store:

• Lab:  Determining Percent Composition

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🧪  Materials for the Percent Composition Lab:

It is a good day for the chemistry teacher when these are the only lab supplies you need. 

• Baking soda 
• 2N sulfuric acid (which equals 1M for sulfuric acid)
• A spot plate
• A Beral pipet (or basically any dropper)
• A laboratory balance
• A test tube

That's it. That’s literally the entire supply list. 🎉

No hunting for exotic lab supplies. No prepping for hours. Just good, clean chemistry (well, mostly clean... there might be a little fizz).

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🌟 What's Happening Here?

Students are going to figure out the percent composition of carbon in baking soda (fancy name: sodium bicarbonate, NaHCO₃). The percentage composition of a compound is the percentage by mass of each of the elements in the compound.  

When you mix baking soda with sulfuric acid, it bubbles and fizzes as carbon dioxide gas is released. According to the Law of Definite Proportions, the mass percentage of carbon in the bicarbonate will be constant, no matter how much sodium bicarbonate is used in the experiment.

Students simply weigh out an amount of baking soda. Drops of 2N sulfuric acid are added to the baking soda, one drop at a time. The reaction releases carbon dioxide. Students continue adding drops of acid until there is no further reaction.  

 

The mass of the apparatus is taken both before and after the completion of the reaction to determine the amount of carbon dioxide that has been released. From the mass of carbon dioxide released, students can mathematically determine the amount of carbon in the released sample, and therefore the percent composition of carbon in sodium hydrogen carbonate.

The student will determine the percent composition of carbon in sodium hydrogen carbonate, both experimentally and theoretically. The student will then determine his/her percent error.

How to Calculate Percent Composition

Percent composition tells you the percentage by mass of each element in a compound.

The formula for percent composition is:

Percent composition = (mass of element ÷ total mass of compound) × 100

In this lab, students determine the mass of carbon indirectly by measuring the mass of carbon dioxide released during the reaction between sodium bicarbonate and sulfuric acid. Using this data, students calculate the percent composition of carbon in sodium bicarbonate and compare their experimental results to the theoretical value. Students learn how to find mass percent using real experimental data, making the concept more meaningful and easier to understand.

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🔥 Why This Percent Composition Lab Works So Well

• Students see the chemistry happening right before their eyes.
• It locks in the concept of percent composition.
• It reinforces the calculations that are being taught in the classroom.
• Supplies are so basic you probably already have them.
• Setup and cleanup are a breeze.
• Real data + theoretical values = perfect chance to teach percent error.
• Safety? Easy. Goggles on, and you're good to go. (Dilute acid = low drama.)

And did I mention? Students LOVE the bubbling. LOVE. IT.

You can find this lab and other related resources in my TPT store:

• Lab: Determining Percent Composition

Frequently Asked Questions About Percent Composition

What is percent composition in chemistry?

Percent composition is the percentage by mass of each element in a compound.

How do students calculate percent composition?

Students divide the mass of the element by the total mass of the compound and multiply by 100.

Why is percent composition important in chemistry?

Percent composition helps students understand chemical formulas, stoichiometry, and mass relationships in compounds.

If your students are ready to apply percent composition in a new way, this composition of a hydrate lab activity helps them determine the percentage of water in a hydrate and use that data to calculate the compound’s formula.

If you are looking for more easy-to-implement chemistry labs, you may also like this Flame Test Lab, where students observe electron energy levels through color changes.

Before diving into more advanced chemistry calculations, it helps if students have a strong understanding of the mole. This blog post reveals a mole lab for high school chemistry that gives students hands-on practice with mass, moles, and Avogadro's number. 

Flame Tests Chemistry Lab for High School | Flame Test Experiment Guide

Flame tests are a classic high school chemistry lab that allow students to identify metal ions based on characteristic flame colors. In this flame test chemistry lab, students observe how different elements emit distinct colors when heated, helping them connect atomic structure, electron energy levels, and atomic emission to real laboratory observations. This flame test experiment is easy to set up, highly visual, and consistently engaging for high school chemistry students, making it an ideal lab for teaching electron configurations, periodic trends, and the behavior of excited electrons.

This flame test lab is an absolute favorite of mine and a much loved lab by all of my students. The best time to use this lab is when teaching atomic structure, electron configurations, energy levels, ground state, and excited state.  

TLDR? Go straight to my TPT store to view this flame test lab.

What is the purpose of a flame test?

A flame test is used to detect the presence of certain metal ions. The test involves heating a sample of the element and observing the resulting color of the flame. When atoms of elements are heated to high temperatures, some electrons may absorb enough energy to allow them to move to higher energy levels. The element is then said to be in the "excited state." This excited atom is unstable, and the electrons quickly return back to their positions of lower energy or their ground state. As the electrons return to their ground state, the energy that was absorbed is given off in the form of visible light. The color of this light can be used to identify the elements involved. In a flame test, the element will give off a characteristic color that serves as a simple method of identification of that element.   

Purpose of the Lab:

• To observe the characteristic colors produced by metallic ions when heated in a flame.
• To identify an unknown metallic ion by means of its flame test.
• To identify the components of a mixture using cobalt glass.

Required Materials:

Bunsen burner, Lab apron, Wood Splints, Safety goggles, Unknown solutions, Test Tubes, Cobalt glass squares, Test Tube Racks, Nitrate solutions of sodium, potassium, lithium, calcium, strontium, barium, and copper.

Step By Step Procedures, Tips, and Suggestions

• I like to set up different lab stations and have the students rotate through the stations. I set up stations for the 7 different metal ions that I will have the students test. Students are required to rotate through these 7 stations first. The standard flame test procedure helps students identify metal ions based on characteristic flame colors.
• After the students have identified the colors of the above 7 metal ions, I assign an unknown for them to identify.  
• Finally, I have the students use cobalt glass to identify the components of a mixture.

• I have used metal inoculating loops as a means of heating the metal ion sample, but I prefer to use wood splints. They are cheap and disposable. Be sure to soak them in the metal nitrate solutions prior to the start of the lab. 

I set up individual lab stations for each metal ion and have students rotate through the stations. 

In a flame test, the element will give off a characteristic color.  It is difficult to catch on camera, but the photos in this post show the characteristic colors of barium (lime green) and lithium (crimson).

 

After students have observed all colors, I assign them an unknown element to identify. 

Using cobalt glass, students determine the identity of elements in a mixture. 
When viewing the flame test with the naked eye, the student will see the yellow color of sodium.
When viewing the flame test while looking through the cobalt glass the student will see the violet color of potassium.

To me this lab serves a greater purpose than just learning to identify metal ions from their flame tests. This lab gets my students so excited about chemistry.... and that excitement makes all the difference in the world when trying to teach chemistry to high school students.

This lab is in my TpT store and can be viewed at this link.

Flame Test Lab FAQs

What is the purpose of the flame test lab?
The purpose of the flame test lab is to help students identify metal ions based on the characteristic colors they produce when heated in a flame. This lab reinforces the concept of electron excitation and emission while giving students hands-on experience with atomic structure and spectroscopy concepts commonly taught in high school chemistry.

Why is cobalt glass used in a flame test?
Cobalt glass is used in a flame test to filter out the intense yellow light produced by sodium ions. Because sodium is commonly present as a contaminant, its bright emission can mask other flame colors. Looking through cobalt glass helps students more clearly observe the true flame colors of other metal ions.

Other Chemistry Labs Your Students Might Enjoy

If you're looking for additional hands-on chemistry labs for your students, you might also enjoy this percent composition lab, where students use experimental data to determine the composition of a compound.

Another engaging activity students enjoy is this mole concept chemistry lab, which helps students visualize and understand the mole through hands-on investigation.

Students can also explore chemical formulas experimentally in this composition of a hydrate lab, where they determine the water content of a compound using real laboratory data.

Have Fun Teaching!