Category Archives: Chemistry Lessons

pH Scale Activity Sort

Posted on by mysciencelessons

To introduce the pH scale, I created a partnered activity where students would place an example for each pH value according to 15 clues that were provided. Each student had a pH scale that I had printed on the color laser printer at school and had pre-cut for them. They glued it into their notebook, towards the edge of the page.

On card stock, I printed the same pH scale in color. I also printed out the 15 examples and cut them apart so that each one formed a rectangular tab.  To keep things organized, I labeled the plastic bag with the group #, and wrote that same group # on the back of each tab so that if they fell out or got mixed up, I could place the sets back together again.

To start the activity, I handed each person the colored pH scale to glue into their notebook.  When they were done, I had them close their notebooks and put them under the table so they had room to work. Then I handed out the cardstock version of the pH scale and one bag for each set of two students.  They removed the tabs from the bag , spread them out, and counted to make sure they had 15. We reviewed where the acids were (pH less than 7) and where the bases were (pH greater than 7). I explained how I was going to read clues and they had to place the tabs into the correct spots on the pH scale and, at the end, we’ll see how many they got right.  (It was like a game, not for a grade)

I read the clues and they worked with their partners to place the tabs where they thought they belonged. After the last clue, I gave them a minute to finish their pH scale and ask for repeated clues if they needed to.  Once everyone was ready for the answers,  I told them that if their tab was in the right spot, to leave it there, and if it was wrong, just slide it to the side. Do not make any changes. I revealed the tab that belonged to each pH value one at a time. At the end, we took a survey to see which partners had the most right. Some kids got 13/15, some had less than 10 correct.

We cleaned up  and took out our notebooks.  On the SmartBoard, I pulled up the answer key and we copied the answers next to each pH value.  Once their notebooks were up to date, I played the BrainPOP movie about the pH scale. I then handed out the activity page and they glued it into their notebooks. With a few minutes left in class, they started their hw.

The kids listened carefully to the clues, they collaborated with their partners, they used information from the pH scale to place their answers, and they wanted to do well. It was funny, when they got an answer right, they whispered ”yes!” and anticipated the next answer to see how many they would get correct.

Notebook:

  • pg. 114 – pH Scale Activity Sort
  • pg. 115 – BrainPOP pH scale activity
  • BrainPOP Movie: pH Scale

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    Law of Conservation of Mass

    Posted on by mysciencelessons

    What I love about this lab: 

    • brush up on TBB skills
    • following directions skills
    • making observations
    • observing a chemical reaction
    • formation of a gas
    • mass of a gas
    • an endothermic reaction, bottom of flask gets pretty cold!
    • reading a chemical equation – shows that same elements are present before and after the reaction, no new elements are introduced or formed.
    • formation of new molecules, the atoms are rearranged to form new substances that were not in the flask before.

    The one thing that is not very clear to the kids is that the mass of the system before the reaction and after the reaction should be the same. Their results consistently show a loss of about 1 gram (on average) without releasing the gas from the balloon. When the gas was released, there was an additional loss of about 1 gram.  

    For this experiment, there are 2 factors that can make the final mass different. The first factor may be leakage: gas, liquid, or both escaped during the active part of the chemical reaction. The seal formed where the balloon meets the flask may not be 100% airtight, even with the kids holding it. But if leakage does not happen, the second factor is buoyancy. When the balloon fills up with CO2, the volume of the balloon increases, therefore displacing the air around it. NSTA published a study about this and had results to show that there was a relationship between the volume of the balloon and the decrease in mass for the closed system.

    Here is an excerpt from the published article: “Because the apparent loss of mass is not due to leakage, this relationship clearly demonstrates a buoyant effect. Archimedes’ principle states that any object submersed in a fluid will displace a volume of fluid equal to the volume of the object and the mass of the object will be reduced or “buoyed up” by an amount equal to the mass of the fluid displaced. Hence, when measuring the mass of an object in air (a fluid) on a balance, the mass that is measured is the conventional or apparent mass of the object. The true mass of the object would be the mass that would result if the object were massed in a vacuum.” (Science Scope, 2008)

    A better example to show conservation of mass may be to place an ice cube or two in a small plastic snack bag, and to take timed measurements as the ice cube melts. (In a humid classroom, condensation forming on the outside of the bag could alter results.) Also, if using baking soda and vinegar, using a soda bottle without the balloon and capping it would keep the volume the same.

    Overall, the kids enjoyed this experiment and it covered a lot of concepts that we studied. If you have done either of these experiments, please share your results!

    Notebook:

  • pg. 110 – Law of Conservation of Mass
  • pg. 111 – Conservation of Mass Analysis

    • Acids & Bases Venn Diagram, Notes

    Posted on by mysciencelessons

    Group SmartBoard Activity (25 minutes): For this activity, I broke it up into 5 parts.

    Part 1: General Discussion about acids and bases, pH, and indicators.  Most 5th graders didn’t really have a lot of prior knowledge on this topic.

    Part 2: Explained how they were going to watch a BrainPOP movie on acids and bases, and to listen for facts presented in the movie.  Using the list of facts on their handout, they were to write an “A” next to the facts that related to acids, and a “B” next to facts that related to Bases.

    Part 3: Gave the students about 3-4 minutes to compare their fact lists with their lab partners. They may not have all the facts categorized, and that was ok.

    Part 4: I explained how one person from each group was going to come up to the board and drag one fact into the Venn Diagram.  If they were correct, everyone wrote that fact into the Venn diagram on their handout.  Students had to choose who would go up for each turn, and what fact they would place. It was a good opportunity for collaboration and coming to a consensus. If the answer was incorrect, they had to drag the fact back to the bottom of the board.

    Part 5: Go over all the answers, make sure that their notes reflected the  notes that were on the board.

    The activity worked really well, the students were on task and it was a nice way to introduce new information in an interactive way.

    I uploaded the notebook file to SMART Exchange, not sure if its fully functioning yet, here is the link.

    Notebook/Links:

  • BrainPOP Movie – Acids and Bases
  • pg. 112 – Acids/Bases Venn Diagram
  • pg. 113 – BrainPOP – FYI – Gastric Acid

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    Balancing Equations

    Posted on by mysciencelessons

       

    Last week I showed the kids how to balance chemical equations. We used a lesson that I started using about 13 years ago when I  taught 6th grade.  Last year I thought I’d have the 5th graders try it, and was really impressed with how quickly they got the hang of it. This years class was balancing equations like pros, too!

    By this point in our lessons, the kids are very familiar with recognizing element symbols, counting atoms, and reading chemical formulas.  I showed them how chemical equation have two sides: products and reactants.  I also introduced the “yields” symbol and how to read an equation. Having the laminated cards, as well as the color coding, allowed the students to process the information visually, tactilely , mathematically, and verbally.

    They worked in pairs to set up and solve the equations. I introduced the first equation to the class and how to count the atoms on either side of the yield sign.  Then I explained that it was like solving a puzzle, or balancing a see-saw.  You want the same amount of “stuff” on either side.  And the only way to solve it, was pretty much by trial and error and don’t be afraid to make a mistake. I also explained that only the coefficients could be added to the front of a molecule, and they couldn’t change the subscripts.

    At first, they were a little intimidated and looked at me like “OMG, this is impossible!” I told them they could do it, just relax, try it, and then ask me for help if you get stuck.  With a little encouragement, they got started and once they solved the first one on their own, they were on a roll!  They worked at their own pace and solved the equations in any order they wanted.   I didn’t expect them to finish all the problems, but most kids solved 70% of the problems, those that worked faster did more, and those that needed more time, did less. I floated around the room and monitored, checked work, and helped as needed.

    The students called me over when they had a balanced equation so I could check their work before they moved on to the next problem.  The kids were on task, talking about the equations, setting up equations, placing the coefficients into the equations and quickly swapping them out as needed, and they were excited. It was almost like a game for them.  For some of the kids, they could just look at the equation and figure it out in seconds!   

    Notebook/Links: 

       

     

    Updated Notebook Pages

    Posted on by mysciencelessons

    Here are some updated pictures of the notebook that we use: 

    Notebook resources:

    Molecular Models – Stations Activity

    Posted on by mysciencelessons

    In the past few weeks, we learned about the periodic table, atoms, Bohr diagrams, Lewis structures, and bonding.  The kids are really comfortable with using the periodic table and we’ve been having fun with it.  Below is a list of teacher lead activities that we completed.  We also enjoyed the Periodic Videos from our friends in England!

    Today we set up and started our stations lab for building molecular models. I don’t have enough models for everyone to have their own set, so I broke it down and set up stations for the kids to build them.  I also added some “make your own” for those pairs of students who are waiting for one of the other stations.

    The kids will rotate through the stations making 3-4 molecules per station. For the Lewis Structures, I have the students try it, if not, they just draw the Lewis Structure for the individual atoms.  For a 5th grader, drawing a Lewis structure for more than 2 atoms bonded together is a tough concept.

    Below are some pics of how I set up the stations.  I am using large 4×6 colored index cards for the stations. Glucose is a challenge station, each year I have one or two groups figure it out with only one or two clues from me.  I don’t tell them its a ring structure, my clue is that it’s not a straight chain.

    Notebook resources:

    Atoms Family

    Posted on by mysciencelessons

    “The Atoms Family” is an activity I have used many times and I still enjoy, and the kids get a kick out of it.  There is a great power point to go along with it and I reformatted the handouts to fit into their interactive notebooks.  I did find a great video clip that another teacher posted showing her class singing the song.

    After we sang it, I showed the video to my classes and they thought it was so cool to see these older kids singing the same song. We then did the Atoms Family Math handout. After doing a problem together, I had volunteers come up to the SmartBoard to solve the problems while everyone else tried them on their own, checking their answers with the ones on the board. After the first few problems, they worked at their own pace, and I checked their answers individually.

    To glue the handout into the notebook, I folded over the whole left edge into a 1/2 in tab and showed them how to glue the tab part into their notebook so that the handout was attached to the page and they were able to flip the handout back and forth to see both sides. 

     

    Here are the handouts and ppt:

    Atomic Model Timeline Foldable

    Posted on by mysciencelessons

    Using a great power point I found online, I created this atomic model timeline foldable to go along with it. The person who made the ppt, used images from the BrainPOP movie for the atomic models and scientists, and an image of Bohr from an episode of the Simpsons .  I photocopied it so that it would be 2-sided. The students then folded it in half using the ”hot dog” fold and cut along the dotted lines to make flaps that lifted.

    As we discussed the power point, they took bulleted notes on the flap for each model/scientist.  We also talked about how Bohr worked on the Atomic Bomb during WW2, about Einstein’s letter to Roosevelt, the race against the Germans to build the first atomic bomb, and the bombing of Japan.  Next time we meet, I want to show some quick  video clips from the movie “Fat Man, Little Boy” and actual footage from the Trinity testing.

    One of my personal goals this year was to incorporate more history and information about these fascinating people into our studies.  In the past I always felt like I didn’t have enough time, but this year I am weaving it in and it doesn’t really take up as much time as I thought it might.

    After break, I will take some pics of completed timelines and the jigsaw activity we did with notes from the BrainPOP Movie.

    Here is the timeline: Atomic Model Timeline Foldable

     

    Chromatography

    Posted on by mysciencelessons

    Just wanted to post this quickly.  We completed a chromatography lab using coffee filter paper and washable markers.  We were able to show how to physically separate a mixture. Each student received one piece of filter paper with a black marker spot on it.  Since I only had one black marker, I prepared all the filter papers.  It was easy and quick to do, I could prepare three at a time, the marker bleeds through from the top layer.  I wanted to use the black as a control so that all the students could have a reference.  Each student then chose two colors to place next to the black dot.

    You can use water if you don’t have rubbing alcohol, it doesn’t really change the results much.  Each student had a paper cup and poured in about 15 mL of water, it didn’t have to be exact.  They slowly placed their filter paper into the cup, being careful not to let the paper fall into the cup.  It contaminates the water and the student will have to start all over again with a new piece and clean water.  I also showed them how to fold over the top of the paper over the lip of the cup to help it stay in place.

    Students were to represent what their filter paper looked like in their lab sheet and make observations.  Once they were done, we let the papers dry (have students write their names in pencil at the top of the filter paper) and then attached it into their notebooks.  Analysis questions were written into the right page of their notebook.

    Handout: