Gas Laws Mini-Unit Review

In preparation for the Mini-Unit 3 Exam tomorrow, students had the class period to:

  • Review for the exam
  • Complete Dry Ice Sublimation lab report
    • Due tomorrow at 11:59 PM – no exceptions
    • Share Google Doc with Mr. Swart
  • Complete and turn in all late Unit 3 work (60% max credit)
    • Due tomorrow – final deadline
  • Work on Honors projects
    • Due tomorrow – no exceptions

The notes below are provided to help students begin preparing for the exam tomorrow.  Students should ask all the questions today!  Do not wait until the test tomorrow to realize you need help.  Office hours are after school today until 3:00.

Combined Gas Law
Combined Gas Law
Ideal Gas Law Flow Chart
Ideal Gas Law Flow Chart
Practice conversions (grams to moles to molecules to atoms)


Week 24

Monday, February 24, 2020 (HS-LS3-1): Today is the final day of class to work on the Chromosome Project slide deck.  For this project, students were tasked with investigating a chromosome and at least 5 genes located on that chromosome.  A complete slide deck will include the following information:

  • Chromosome number
  • Brief description of what happens with too many or too few copies of the chromosome
  • For the gene you researched the most (and have trait information for):
    • Official Symbol
    • Official Name
    • Your own one-sentence summary of about the protein the gene codes for
    • Location of the gene on the chromosome
    • Number of exons in the gene
    • Length of the gene (in DNA bases)
    • Length of the protein (in amino acids)
    • Description of trait and how that is connected with your gene
  • Research information for the other 4 genes you investigated
  • Citations for the information you gathered so anyone else can repeat your findings.

Tuesday, February 25, 2020 (HS-LS3-1): It’s Chromosome Project “Poster” Walk day!  Time to share what was learned about each chromosome and learn about the amazing diversity of genes on each and the traits those genes code for.  Students will present their slide decks to each other in small groups while completing the poster walk handout.

Wednesday, February 26, 2020: Unit 3 Review – Notes from class shown below

Thursday, February 27, 2020: Unit 3 Exam

Friday, February 28, 2020: To conclude Week 25, and in preparation for our next unit, we watched the first 30 minutes of  Some of the Things That Molecules Do (Cosmos, episode 2), pausing periodically to answer questions on the handout students received and which will be turned in after we complete the video tomorrow.  During the video, students learned:

  • wolves and dogs share a common ancestor (artificial selection);
  • brown bears and polar bears share a common ancestor (natural selection);
  • how random DNA mutations can occasionally produce desirable traits depending on the environment in which the organism with the mutation lives;
  • how all life on Earth is connected via DNA to a common ancestor (using the Tree of Life analogy);
  • how the evolution of sight can be traced all the way back to bacteria

Week 23

Monday, February 17, 2020: No School (Mid-Winter Break)

Tuesday, February 18, 2020 (HS-LS3-1): So far this unit, we have reviewed Central Dogma, reviewing how DNA codes for RNA which codes for proteins which ultimately determine our traits.  We learned about the structure of genes, including the regulatory region that turns genes on and off, as well as coding regions (exons) and non-coding regions (introns) which are excised during the processing of precursor RNA to messenger RNA (mRNA).  We learned that unlike mitosis (the process in which a parent cell divides to make two identical diploid copies of itself), during meiosis a parent cell divides to ultimately produce four haploid gamete cells (eggs and sperm), each with a random assortment of chromosomes that vary somewhat from each parent chromosome because of the process of crossing over.  We watched a video depicting the process of fertilization, picking up the story following the introduction of male sperm into the female reproductive tract, and learning for out of 300 million sperm, only one sperm ends up fertilizing an egg, thus kicking off the process of countless rounds of mitosis to produce a new individual.  Finally, we constructed one- and two-trait Punnett Squares to predict and analyze the inheritance patterns of traits passed along from two parents to their offspring.

To move our learning forward, we will focus on the chromosomes.  Humans have 23 pairs of chromosomes, 22 pairs of autosomal chromosomes and 1 pair of sex chromosomes (XX = female and XY = male).  During the process of mitosis and meiosis, the chromosomes are copied and moved to the newly divided cells.  In mitosis, the 23 pairs of chromosomes (46 total) are copied exactly, resulting in two new cells, each with the same set of 23 pairs of chromosomes.  In meiosis, the successful result of meiosis II is the production of four cells, each with individual copies of chromosomes 1-22 and one of the sex chromosomes (23 total chromosomes).  However, sometimes the chromosomes don’t separate out perfectly.  In many cases, if one of the four daughter cells of meiosis II has an extra copy of a chromosome because they fail to separate (non-disjunction), and another cell is missing a copy of a chromosome because it went to that other cell with two copies, both cells will be non-viable.  However, there are well-documented cases where having an extra copy of a chromosome results in a viable human.  One example is called Trisomy 21, or Down Syndrome.

For our work today, we discussed the first three slides of the Down Syndrome Case Study slide deck and then detoured to the Wikipedia entry on aneuploidy.  We focused on the Types section of the entry, examining how, of the autosomal chromosomes, only Trisomy 21 will result in a viable fetus most of the time.  Students learned that when trisomy occurs in most of the other autosomal chromosomes, the result is an embryo that is non-viable, often resulting in miscarriage.

Back to the Case Study!  To learn how Trisomy 21 occurs, students watched a short video illustrating non-disjunction.  To put a human face on Trisomy 21, or Down Syndrome, students watched another short video about two young twins with Down Syndrome.  Both videos are shown below:

The second video naturally leads to questions about twins, so slide 5 explains the difference between identical and fraternal (non-identical) twins.  After slide 5, students will have time to read a Newsela article about possible a possible new treatment for Down Syndrome. After reading the article, students will respond to the writing prompt in the “Write” section of Newsela.

Wednesday, February 19, 2020 (HS-LS3-1): Welcome to the Chromosome Project!  You have the exciting opportunity to study a chromosome and learn about the genes that exist on a chromosome.  The goal of this project is to help you make a clear connection between DNA, genes, chromosomes, traits, and inheritance.

Your goals for today are:

  1. Check your student gmail to determine which chromosome you are assigned to research.  Autosomal chromosomes = 1-22 and the sex chromosomes are X and Y.  One you know your chromosome, a link to a list of all of the Chromosome Project Google Slide decks is located hereFor security, only students working on a specific chromosome may view and edit the slides for that chromosome.
  2. Research and write down what happens during human development if more than two copies of the chromosome are present.  What happens if only one copy of the chromosome is present?  Be sure to document your sources!  One resource is the Wikipedia entry on aneuploidy.
  3. Conduct a search for “genes on chromosome____” and insert your selected chromosome.
  4. Research at least 5 genes on your chromosome.  Research = write it down!  You must document your work to receive credit.  For each gene, write down the key information about each gene.  How?  Read below:

To research your gene, visit the NCBI Human Genome Resources page and enter your gene name into the “Search For Human Genes” box.  When the search completes, click on your gene name (typically the first gene on the list) and browse through the entry.  There is a ton of information provided!  For each gene, write down the following:

  • Official Symbol
  • Official Name
  • Your own one-sentence summary about the protein the gene codes for
  • Location of the gene on the chromosome
  • Number of exons in the gene
  • Length of the gene – hover your mouse over the top green line under the “genomic regions, transcripts, and products” and looking for the number after the aligned length (nt = DNA nucleotide bases) 
  • Length of the protein – hover your mouse over the top green line under the “genomic regions, transcripts, and products” and looking for the number after the protein length (aa = amino acids) 

Thursday, February 20, 2020 (HS-LS3-1): Select one of the genes from your list.  Research one trait associated with that gene and explain the connection between the gene and the trait.  For your final work, create a Google Slide with the following information:

  • Chromosome number
  • Brief description of what happens with too many or too few copies of the chromosome
  • For the gene you researched the most (and have trait information for):
    • Official Symbol
    • Official Name
    • Your own one-sentence summary of about the protein the gene codes for
    • Location of the gene on the chromosome
    • Number of exons in the gene
    • Length of the gene (in DNA bases)
    • Length of the protein (in amino acids)
    • Description of trait and how that is connected with your gene

Friday, February 21, 2020 (HS-LS3-1): Work day – continue your research and the Google Slide for your chromosome.

Ideal Gas Law Lab

Today marks the start of the final week for our gas laws unit.  Class began with an entry task in the form of an ungraded Google Form quiz.  With our Unit 3 Exam scheduled for Friday, the quiz provides students with yet another opportunity to self-assess, and the results will help us focus our review as the week progresses.

For our work today, in preparation for our lab tomorrow, students will review the diagram below which illustrates the connection between the three phases of matter commonly encountered on Earth, and the vocabulary associated with changing phase.  Click on the image to learn a whole lot more about the science of phase change.

To help students visualize the least familiar of the phase change reactions (the solid-to-gas and gas-to-solid phase changes), we will watch a brief video below, complete with spooky soundtrack:

Next, students created a Google Doc and began pre-writing the Lab Report for the lab tomorrow in which we will actually conduct the experiment described in the entry task.  The intent is that students will follow their written Procedure tomorrow, collect data for the Results section, and understand the purpose of the lab (Introduction) so evaluating results in the Conclusion section will occur smoothly on Wednesday.  Lab reports will consist of:

  • Student name
  • Lab report title (Dry Ice Sublimation Lab)
  • Introduction (explain the purpose of the lab, including the connection between dry ice, sublimation, volume, and the Ideal Gas Law)
  • Procedure (numbered list of steps someone could follow to recreate your experiment)
  • Results (observations from the lab, focusing on mass and volume)
  • Conclusion (what was learned, comparison of calculated volume vs measured volume, three potential sources of error, and solutions to correcting those sources of error in the future)

Class Notes:

For homework, students received the Lesson 64 Worksheet to work this evening in preparation for class tomorrow.

For the second lesson of the Gas Laws mini-unit, students worked with dry ice and watched a couple of teacher demonstrations involving dry ice.  To begin class, students worked in small groups to measure the mass of a small amount of dry ice, quickly transfer the dry ice into a balloon, and then quickly tie off the balloon to trap the sublimated carbon dioxide gas. Students then measured and recorded the mass of the dry ice added to the balloon at the beginning and at the end of the experiment, then measured the volume of the bag after the dry ice finished sublimating in order to calculate the density of carbon dioxide gas.

While waiting for the dry ice to sublimate, students hypothesized about what they might observe when water ice and dry ice were heated on a hot plate, and also what would happen when water and dry ice were added to liquid water or vegetable oil (pictured below).

Dry ice in vegetable oil (left) and water (right)

Class Notes:

Note: For students who missed class due to testing today, please watch the videos below as a substitute for participating in the lab.

For the final day of this lesson, students need to finish writing their lab report (Google Doc, shared with Mr. Swart) detailing their results from the dry ice in a balloon experiment.  The lab report must include the following clearly labeled sections:

  • Introduction (explain the purpose of the lab, including the connection between dry ice, sublimation, volume, and the Ideal Gas Law)
  • Procedure (numbered list of steps someone could follow to recreate your experiment)
  • Results – observations from the lab, including:
    • initial mass of the dry ice converted to moles of CO2
    • initial and final mass of the dry ice and balloon
    • final volume of the balloon as measured during the lab
    • calculated volume of the balloon using Ideal Gas Law (PV=nRT)
    • amount of time it took the dry ice to fully sublimate in the balloon
    • calculation of the rate of sublimation (mass of CO2 divided by sublimation time
  • Conclusion: Compare the volume measured via the Ideal Gas Law to the volume measured during the experiment.  Explain why the numbers are different.  Suggest at least two possible sources of experimental error.

The Mole and Avogadro’s Law

We continued our learning of gas laws by taking the combined gas law and adding in the concept of the mole to account for the number of particles contained within a sample of gas.  We began with class notes (pictured below).  Then, students were assigned to read Lesson 64 of our textbook: The Mole and Avogadro’s Law.  Students then worked in groups of 3-4 to complete the Exercises at the end of Lesson 64 (responses due by the end of class).  The Lesson 64 PowerPoint is provided for reference material. To conclude the class period, students received back their quiz from last Thursday.



For day 2 of this lesson, students were greeted with an Ideal Gas Law entry task (solutions pictured below) which consumed the majority of the abbreviated class period.

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For days 3 and 4 of this lesson, students were first tasked with completing the Lesson 64 Exercises from Tuesday, then working on the Moles Gizmo.

Additionally, students received a paper copy of Ideal Gas Law Practice Problems (pages 1-2 of the linked document).  Click the link and scroll to page 3 for the solutions to check your work.

Notes from class:

Extend Your Learning!

Interested in how scientists calculated the number of particles in one Mole?  Read about it at Wired Magazine.

Air Pressure

Our day begins with an entry task instructing students to watch the video below of a lava lamp, then explain the action of the lava lamp using volume (V), temperature (T), and pressure (P).

Student ideas:

200210 Chemistry Lava Lamp Picture

After discussing student ideas, students watched the short video of hot air balloons inflating and flying.  They were challenged to explain why hot air balloons fly, why they rise to a certain height and then stop, and how hot air balloons change altitude.

After a brief discussion, students were introduced to some new vocabulary terms included in the Lesson 57 PowerPoint.

Class Notes:

200210 Chemistry Balloon Picture

Finally, students rotated through four different stations to make observations and collect data on a modeling air pressure lab handout helping them to learn more about air pressure.

Station instructions:

Notes the next day showing molecule motion in the experiments

Keep Learning (at home!): Balloon in a bottle

Week 22

Monday, February 10, 2020 (HS-LS3-3): We kicked off the short week with an entry task designed to reinforce the concept of independent assortment and introduce the idea of dihybrid crosses (two trait Punnett Squares).  Students each received two coins: a penny and a nickel.  Each coin represented a different chromosome.  Heads represented the dominant allele of a gene (P or N) and tails represented the recessive allele (p or n).  Students were tasked with identifying the 4 possible allele combinations of the two genes (PN, Pn, pN, and pn).  Next, we constructed a dihybrid cross to determine the 16 possible allele combinations between two heterozygous parents (PpNn x PpNn).  Class notes are shown below:

200210 Biology Pic 1

200210 Biology Pic 2

Students had the remainder of class to complete the One-Trait Gizmo from last week and then to work through the Two-Trait Punnett Square Gizmo which included an additional review and application of the vocabulary learned thus far.

Tuesday, February 11. 2020 (HS-LS3-3): Class began with the following entry task:

Set up, filled in, and analyze the three one-trait Punnett Squares below, then complete a dihybrid cross for two parents with genotypes AaBb and AaBb.

Finally, students had the remainder of the class period to work through all unfinished work.  Students will be quizzed on one and two-trait Punnett Squares on Thursday.

Keep Learning!

Review dihybrid crosses by watching the video by Mr. Anderson of Bozeman Science:

Wednesday, February 12, 2020 (HS-LS3-3): Today is the final work day this week.  All work from this unit is due today for full credit.  Students should carefully study their notes for the quiz tomorrow.  Students who have additional time are challenged to construct, solve, and analyze a tri-hybrid cross for three independently assorting genes (penny, nickel, and quarter) where both parents are heterozygous.

Entry Task:

Student Examples of Trihybrid Crosses (Wow!):

Trihybrid Cross Example 1

Trihybrid Cross Example 2

Trihybrid Cross Example 3

Thursday, February 13, 2020 (HS-LS3-3): Punnett Square quiz

Friday, February 14, 2020: No School (Mid-Winter Break)

Combined Gas Law

We began class with a brief review of the gas pressure experiments from yesterday.  Students shared results and ideas, then updated their models and explanations.

Next, having thoroughly explored gas laws involving two variables (Pressure & Volume, Pressure & Temperature, and Temperature and Volume), students were introduced to the Combined Gas Law, k=PV/T.  We began class with the video below:

For our work today, students were tasked with reading Lesson 61 in the textbook and then working through the Lesson 61 Worksheet.  For additional practice, students should work through the exercises at the end of Lesson 61 in the textbook.   

Week 21

Monday, February 3, 2020 (HS-LS3-1): We took notes on the structure of genes, including a review of how chromosomes are found in the nucleus of cells, how chromosomes consist of DNA coiled around histone proteins, and how genes consist of regulatory regions, exons, and introns.

Biology 200203 Picture

Class concluded with the Crash Course video about heredity (below).  We paused strategically to capture important vocabulary terms (diploid, haploid, somatic cells, gametes) which were added to our vocabulary list from Friday.

Tuesday, February 4, 2020 (HS-LS3-2): To begin class, we watched the Amoeba Sisters video about meiosis (below) and students worked through a guided worksheet.

After the video, students had the remainder of class to read pages 52-59 of Inside the Cell to help them complete the Amoeba Sisters worksheet and to investigate the processes of independent assortment and crossing over.  Students answered the “Got It?” questions on page 59 of the book in their lab notebooks.

To demonstrate evidence of understanding, students were tasked with creating a stop-motion claymation video or Google Slides explaining the processes of independent assortment and crossing over (shared with the teacher).

Wednesday, February 5, 2020: Today is a continuation of yesterday.  Completed videos or slides depicting independent assortment and crossing over are due today.  Students who finish early should begin working on the One Trait Mouse Genetics Gizmo.

Thursday, February 6, 2020: As we enter the final week of Unit 5: Inheritance and Meiosis, we turn our attention toward the process of reproduction.  Class begins with a video which explains the process of human fertilization.  After a brief class discussion about what was learned and what questions remain, students were assigned a reading from the textbook along with the questions below:

In the BSCS textbook, read “Making More People” (p.477-481)

  1. How many ova are found in the ovaries of a newborn baby?
  2. How many ova mature into healthy ova?
  3. Where and when do ova begin maturing?
  4. Where are mature ova fertilized by sperm?
  5. Where are sperm formed?
  6. How long does it take an individual sperm to develop?
  7. How do sperm obtain the energy to swim through the female reproductive tract?
  8. How and why does the male body regulate testicle temperature?
  9. Explain the difference between a zygote, an embryo, and a fetus.
  10. What determines when a woman is ready to begin labor?

Friday, February 7, 2020: Class will begin with a short quiz focusing on:

  • Punnett Square vocabulary
  • Mitosis and meiosis: similarities and differences

After the quiz, students will have the remainder of the class period to complete and turn in any remaining work from this week.  Students who finish early should work on the single-trait Punnett Square Gizmo handed out last Friday.

Gas Laws Simulation

Monday, February 3: Last week, students were introduced to four different gas laws: Avogadro’s Law, Boyle’s Law, Charles’ Law, and Gay-Lussac’s Law.  We conducted a lab using marbles to determine the effect of volume, temperature, and “molecule” number on pressure.  We also practiced solving problems using Boyle’s Law and learned more about the variables of pressure and volume.

For our work today, students will complete guided notes focusing on Boyle’s, Charles’, and Gay-Lussac’s Laws.  We will also focus in on the variable of temperature, differentiating between Fahrenheit, Celsius, and Kelvin.  Students also received an Exit Task designed to illustrate the process and expectations for solving a gas laws type of story problem.

Notes from class:

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Keep Learning!

Want to know more about Absolute Zero and the Kelvin Scale?  Check out the selection of videos below and expand your mind:

Tuesday, February 4: We will complete our in-depth look at the math and thinking behind Boyle’s, Charles’, and Gay-Lussac’s Laws by completing the notes handed out yesterday.  Students will then begin working through the Gas Laws Simulation and accompanying guided work packet (AACT resource – provided by Mr. Swart).

Students interested in pursuing the Honors Option this semester also received an optional Gases Poster assignment that will be due February 28 and which will be presented to the class that day.  Students may work alone or with a partner.

Class Notes:

Wednesday, February 5: All 10th grade students are out of the building on a career-day field trip.  Non-10th grade students will have the class period to work on the Gas Laws Simulation.

Thursday, February 6: Students will have the entire class period as a work day to complete the Gas Laws Simulation. Students will also receive back their Exit Task from Monday to use as a study tool for the quiz tomorrow. The answer key is provided below:

Note: The quiz tomorrow will include questions about the Gas Laws learned thus far, and will also include math problems that require the sort of algebra reviewed in Monday’s entry task.  Students may use the guided notes from Monday/Tuesday on the quiz.