# Under Pressure – Introduction to Gas Laws

Class began with a brief review of yesterday’s exit task in which students were asked to analyze real data comparing the effect of exam color and having notes on the exam.  The data was graphed as individual dots, and the average (mean) was shown.  The analysis also included the p value for a t-test, and students learned how to interpret the p value in the context of statistical significance.  For details on how to conduct a t-test, see the Keep Learning! section at the bottom of this post.

Our mini Gas Laws unit began with a brief silent video introducing the Gas Laws.  Students were tasked with making written observations and then we held a class discussion and produced a chart of what they Know, Think They Know, and Need to Know.  Next, students were introduced to Robert Boyle, one of the great chemistry scientists from history who contributed greatly to our understanding of Gas Laws. Students completed a guided notes handout while watching the video and discussed responses after.  To watch the video outside of class, request a passcode from Mr. Swart.

Note: Many of the lesson materials for this unit are supplied by the American Association of Chemistry Teachers (AACT) and require a membership to access.

The lesson concluded with a gas pressure simulation lab activity in which students worked in groups to simulate the movement of gas molecules, observing how a changing the temperature, volume, and number of molecules affects the pressure of a gas.

Notes from class:

Keep Learning!

For the second day of the lesson, we began with an entry task in which students were instructed to use Boyle’s Law (PV=k) to solve three different problems, each missing one of the three variables in Boyle’s Law.  Next, we reviewed what went well and strategies for improving the lab we started yesterday based on criteria (lab objectives) and constraints (barriers/realities).  After agreeing on a plan forward, students had the remainder of the class period to work through the modified lab and then finish the analysis questions on the back of the lab handout.

Class Notes:

For the final day of the lesson, students will complete the Friday Quiz (click here!) and then have the remainder of class to complete the lab from yesterday.  For homework, students should analyze any remaining video from the lab and then work through the analysis questions on the back of the lab handout.  Students should also review the PowerPoint (Unit 3 Vocabulary).

# Week 20

Monday, January 27, 2020: No School (Semester Break)

Tuesday, January 28, 2020: Welcome to second semester!  A new semester brings fresh start and a new unit.  Before we dive in, we will roll out a new seating chart, welcome new faces to our classroom, review the class Syllabus and Safety Contract and hold a class discussion around expectations this semester.

Next, we launched Unit 3 (Heredity: Inheritance and Variation of Traits) with the following entry task:

In your lab notebook, list at least 5 traits that best describe who you are.

After responding to the entry task, students worked with their table teams and together they debated whether a list of traits provided on a worksheet are inherited via nature, nurture, or both.  We came back together as a class so students could share their thinking and hear each others ideas.

Class concluded with the following assignment, due tomorrow:

Using your list of traits from the entry task, write an explanation about which of your traits are nature, which are nurture, and which are both.  Explain your thinking!

Notes from class:

Wednesday, January 29, 2020: Yesterday, we debated whether a variety of traits are obtained through nature (DNA) or nurture (culture). During our class discussion at the end of class, we determined the trait of sleep pattern was likely caused by both nature and nurture.  We will begin class with the TedEd video below to provide evidence to support the claim that sleep pattern is indeed a product of both DNA and culture:

In today’s lesson, we used a case study about cystic fibrosis as the mechanism to:

• review Central Dogma (from way back in Week 5!) and introduce the stop codon;
• connect the concepts of protein structure and function;
• bring a human face to a genetic disease;
• and help students recall the mechanism of genetic inheritance.

For the entry task, students were challenged to consider how genes begin and end.  We discussed how mRNA sequences always begin with AUG (which codes for methionine, and amino acid which may also occur elsewhere in a protein).  Students were then reminded of the three “stop codons” and we reviewed how those work to release a protein from the ribosome.  We reviewed the structure of amino acids, focusing on the 20 different R groups and how those R groups each have different properties.  The interactions between R groups determine protein shape, and shape determines protein function.  When the sequence changes, the shape changes, thus changing the function of a protein.  We then moved into the cystic fibrosis case study, first watching the video below and then working through the lesson PowerPoint.

Class notes:

Thursday, January 30, 2020 (HS-LS3-2): For day one of our two-day lesson on the structure and function of genes, we reviewed Central Dogma via the first two slides of today’s PowerPoint.  Next, we dug into the vocabulary of proteins, revisiting words like amino acid, peptide, polypeptide, protein, and peptide bonds.  Students learned that proteins fold into specific structures (shapes) and that a protein’s structure determines its function.  Next, we reviewed the structure of amino acids, and students received a handout with the names and structures of all 20 amino acids.  We drew a model of two amino acids bonding via dehydration synthesis and forming a peptide bond.  We then defined the R group for an amino acid and discussed how each amino acid contributes to the overall shape of a protein.  Finally, we connected this review of Central Dogma back to the idea of traits by considering how DNA mutations can affect proteins, sometimes with drastic consequences.

Class Notes:

Friday, January 31, 2020 (HS-LS3-3): For our entry task today, students worked through the Friday Quiz (click here!) using the class Chromebooks.  After the quiz, we previewed single-trait Punnett Squares to prime students for next week.  Class notes are provided below:

# Semester 2 Launch

Welcome to second semester!  A new semester brings fresh start and a new unit.  Before we dive in, we will roll out a new seating chart, welcome new faces to our classroom, review the class Syllabus and Safety Contract and hold a class discussion around expectations this semester.

Next, students will receive back their graded Unit 2 exams.  We will discuss any questions students have about the exam.  Students who took the Unit 1 exam will also receive it back graded.  Two groups of students took the exam:

• Students with an A after the unit 2 exam was graded had the option of taking the Unit 1 exam.  The exam score does not affect the semester 1 grade.  However, students who earn a 70% or better on the exam will receive an Honors designation on their transcript for 1st semester chemistry.
• Students who did not turn in the Unit 1 Project had the option of taking the Unit 1 exam.  The exam score (up to 60% max) will replace the missing score from the project.

Finally, we will wrap up 1st semester with an Exit Task designed to help them reflect on their successes and consider opportunities to grow during 2nd semester.  After the Exit Task, students should confirm access to the class textbook (full student gmail address and HighlineMM/DD where MM/DD are birth month and day) and the class Newsela account.

# Week 19

Monday, January 20, 2020: Martin Luther King, Jr. Day (No School)

Tuesday, January 21, 2020:

For our final week of the semester and this unit, we refocus the Biome Project through the lens of “rewilding” – restoring an area of land to its natural uncultivated state (used especially with reference to the reintroduction of species of wild animal that have been driven out or exterminated).

After a class discussion focused on gathering student reactions to the concept of rewilding, students were tasked with selecting one or more articles about the topic to read and summarize for their Biome Project team on the team’s Google Doc in the Rewilding, Part 1 section.

Wednesday, January 22, 2020: To conclude this project, it is time to think big. REALLY BIG.  In the Ted Talk yesterday by George Monbiot, he proposes the reintroduction of mega flora and fauna (really big plants and animals) that have gone extinct.  Focusing specifically on your biome on your continent, research really big plants and animals that once lived in your area but have gone extinct some time in the past 10,000 years.  Complete this section in the Team Google Doc in the Rewilding, Part 2 section.

As a group, select one mega flora (huge plant) and one mega fauna (huge animal) to reintroduce into your biome.  Explain how reintroduction of each will impact the ecosystem of your biome.  Complete this section in the Team Google Doc in the Rewilding, Part 2 section.

Next, predict how humans living on your continent in your biome might respond to reintroduction of the mega flora and mega fauna you reintroduced.  How will culture be impacted?  Complete this section in the Team Google Doc in the Rewilding, Part 2 section.

Finally, work together as a team to create a poster describing one aspect of culture as it exists today (before) and as it might exist in the future after rewilding.  The poster should be colorful, creative, and able to be shared with the class on Friday, January 24.

Thursday, January 23, 2020: Work day!  Complete all unfinished work on the Team Google Doc and work together to to create the team poster (see yesterday’s instructions and the Team Google Doc).

Friday, January 24, 2020: For the final day of the semester, and the final day of Unit 2, student groups must turn in a complete poster to display in class next week.  Work together as a team to create a poster describing one aspect of culture as it exists today (before) and as it might exist in the future after rewilding.  The poster should be colorful, creative, and able to be shared with the class on Friday, January 24Posters and Team Google Docs will be evaluated over weekend and credit will be assigned as the last grades of first semester.

# Unit 2 Review

Friday, January 17, 2020: For the entry task, students are assigned the job of accessing the Swart Chemistry Unit 2 Review Google Doc designed to facilitate the unit 2 review process.  Each student is responsible for:

1. Selecting one question from the Unit 2 Review section of the textbook (pages 252-256) and writing both the question (including all multiple choice answers), highlighting the correct answer using bold text, and then explaining why the correct answer is correct along with including a page citation from the textbook.
2. Selecting at least three exercise questions from Lessons 28-48 in the textbook.  The questions are found at the end of each lesson.  Follow the same steps as above.
3. Note: If all Unit 2 Review questions have been addressed, verify one answer (include your name as the verifier) and then answer at least four questions from Lessons 28-48 in the text.

Tuesday, January 21, 2020: For our first day of review for the Unit 2 Exam taking place on Thursday, we briefly reviewed the vocabulary of chiral, achiral, and dehydration synthesis reactions (encountered in Lesson 34) by visualizing the reaction in the context of amino acids.  Class notes are shown below:

Next, students played a Kahoot! designed to test their understanding and retention of material they had the opportunity to study over the three-day weekend.  After the Kahoot!, students had the remainder of the class period to answer or verify answers on the class Google Doc started last Friday.  All students received a copy of a practice test to complete in class or as homework.  In addition, students were reminded to prepare one 8.5″ x 11″ page of notes (front and back) to use on the exam.

• Connection between molecule name, molecular formula, functional group, and smell
• Larger molecule shapes and smells
• HONC 1234 Rule
• Connection between molecule size, polarity, and smell
• Lewis dot diagrams (lone pairs, bonded pairs)
• Molecule shape
• Receptor-site theory
• Electronegativity: calculations, partial charges, dipole, symmetry
• Mirror-image isomers (chiral molecules)
• Amino acids: how are they similar? different? R group polarity

Notes from the white board (click arrows to move through slide show):

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# Amino Acids and Proteins

The final lesson of Unit 2 explores how amino acids connect to make proteins.  The Lesson 48 PowerPoint includes the vocabulary terms of amino acid and protein.  Lesson 48 connects with Lesson 47, as amino acids are chiral molecules.  Notably, all of the 20 different amino acids in human proteins are “left-handed” (as opposed to the mirror-image “right-handed” isomers), meaning they all have the L conformation (L for laevus, Latin for “left”) rather than the D conformation (D for dexter, Latin for “right”).  Students will work in pairs to complete the Lesson 48 Worksheet, learning about the properties of amino acids and how they bind together to form proteins.  For more on the D and L convention, click on the picture below.

As noted previously, there are 20 different amino acids.  All amino acids share the same base structure of a central carbon atom bound to a carboxylic acid (-COOH), an amino group (-NH2), and a hydrogen (H).  The central carbon is also bound to an R group, with R indicating any one of the 20 different amino acid structures.  The structures each have different physical properties.  When individual amino acids link together, a polypeptide chain is formed (and a molecule of water is removed as each new amino acid is linked to the chain).  The polypeptide chain, composed of a string of amino acids, folds into a particular shape determined by the interactions of all of the amino acids.  The shape of a protein determines its function in the body.  Mr. Anderson of Bozeman Science has a fantastic video explaining the nature of proteins:

For students looking for a good review of Central Dogma (DNA > RNA > Protein > Trait), the Crash Course Biology video DNA, Hot Pockets, & The Longest Word Ever is a good resource:

Finally, for students with access to a home computer, the Fold.It website will have you folding proteins in no time!

Homework:

• Write notes for Lesson 48 and work through the practice problems at the end of Lesson 48

# Mirror-Image Isomers

Yesterday, students were introduced to the concept of mirror-image isomers, chiral objects (an object that is not equal to its superimposed reflection), and achiral objects (an object that is equal to its superimposed reflection).  We applied the terms chiral and achiral to real-world 3-dimensional objects all students are familiar with like hands, springs, and barbells:

We then watched a video to more fully understand how to apply those terms to central carbon atoms with less than 4 different groups (achiral carbons) and 4 different groups (chiral carbons):

After the video, we applied drew molecules with a central carbon atom and increasing numbers of attached groups.  Students had the opportunity to build the molecules and their mirror-images using molecular modeling kits in order to better visualize superimposability.

Next, we applied the concept of chirality to molecular smell.  Students smelled extracts containing one of two different mirror-image isomers containing a chiral carbon, finding one to smell like mint and the other like pickles.  This evidence supports the concept of receptor-site theory, where molecules with highly specific shapes are recognized by distinct receptors in the olfactory system, resulting in the perception of distinct smells.

Students then received the Lesson 47 Worksheet, working in pairs to model the compounds using the class set of molecular modeling kits.

Day 2: We will begin class today with an extension of the concept of chirality.  Prior to 1961, scientists did not fully appreciate the profound biological importance of chirality as it relates to medicine.  The tragic story of thalidomide illuminated scientists to a level of chemical complexity not previously appreciated as biologically relevant:

Keep Learning!

Want more?  Check out the blog post Perhaps looking-glass milk isn’t good to drink for an overview of Lewis Carroll, looking-glass milk, and L- and D-carvone.  Want more?  Joanna Shawn Brigid O’Leary from Rice University published an even more extensive investigation of how Lewis Carroll (author of Alice in Wonderland and Through the Looking Glass) weaved biochemistry into his fiction.  Her paper (available as a PDF), WHERE ‘THINGS GO THE OTHER WAY’: THE STEREOCHEMISTRY OF LEWIS CARROLL’S LOOKING-GLASS WORLD is well worth the read.  Perhaps it will even inspire students to read the book before the movie is released in theaters on May 27!

Homework:

• Write notes for Lesson 47 and work through the practice problems at the end of Lesson 47

# Week 18

Monday, January 13, 2020 (HS-LS2-7HS-ETS1-3): Student groups have the class period to meet and write the group consensus sections of the Team Continent Project Google Doc.  By the end of today, teams should reach consensus on which three biomes they want to research for the project, and the list should be numbered in order of preference (1 = top choice, 2 = second choice, 3 = third choice).

Biome Assignments:

• Team Africa: Savannah
• Team Australia & Oceania: Tropical Rain Forest
• Team South America: Alpine
• Team Asia: Temperate Deciduous Forest
• Team North America: Temperate Grassland

Tuesday, January 14, 2020: No school (snow day)

Wednesday, January 15, 2020 (HS-ETS1-4): One of the major learnings from our work last week is that humans have made major changes to the environment, often as a result of using the land to produce food.  As our population increases, farmers and food scientists must find ways to feed more people.  One technique being used is genetic modification.  By altering the DNA of certain crops, traits can be introduced that allow more food to be grown than was possible previously.  Students will work through the Gizmo: GMOs and the Environment.  The Gizmo is designed to “help students weigh the positive and negative effects of growing genetically modified (GM) corn in a farm setting. Students can experiment with different types of GM crops, modify pesticide amounts, and view the resulting corn yields and long-term environmental effects. This Gizmo is meant to simulate the decisions made on a farm and does not endorse the use of GMO crops.”

Thursday, January 16, 2020: Work on the “GMOs and the Environment” Gizmo from yesterday.  The Gizmo is due tomorrow at the end of class.  Students who complete the work should continue to Friday’s activity.

Friday, January 17, 2020: Complete the “GMOs and the Environment” Gizmo.  The Gizmo is due tomorrow at the end of class.  The remainder of class should be spent completing activity 8 on the Continent Team Biome Project shared Google Doc (click the link below for team docs).

Activity 8 on the Team Google Doc asks students to work with their team to complete the following work:

1. Using BiomeViewer, navigate to your team’s continent and identify a region that includes your assigned biome.
2. Next, select the Anthromes view and set the year to 2000.  Look for regions of overlap (biome and anthrome) that show the most human activity.
3. Cross-reference the developed area with a map of your continent showing major cities.  You may need to conduct an Internet search for a good map of the region you are searching for.  List as many named areas as possible in the space below.
4. Using the Anthromes view, describe how the region has changed over time.
5. Conduct an Internet search to investigate how the way people live in the region has changed over time.  Research should include things like diet (what they eat), housing (structures they live in), clothing (common things to wear), work (common ways people earn a living), and entertainment (what people do for fun).  Include pictures as needed and include sources!

# Phase, Size, Polarity, and Smell

Chapter 8 concluded with the Lesson 46 PowerPoint and Lesson 46 Worksheet.  Lesson 46 brought together the various concepts needed to understand how molecules with certain properties can be detected by our noses, with our brain recognizing those molecules as having a specific smell.  The entry task (ChemCatalyst) asks students to model why perfume molecules can be smelled from across a room, but paper cannot (both placed near a sunny window).

Students also received a copy of the Chapter 8 Study Guide to use in preparation for the quiz on Tuesday.  Work through the quiz questions on your own, then compare your answers to the key.

Notes from class (January 10):

Notes from class (January 13):

Keep Learning!

Wondering how to determine whether a molecule is symmetrical or asymmetrical?  Work through the slide deck from Dr. Fred Omega Garces and focus in on slide 15.  Look familiar?  Students received a copy of this flow chart in class today.

Homework:

• Write notes for Lesson 46 and work through the practice problems at the end of Lesson 46

# Polar Molecules and Smell

We continued our study of polarity, this time exploring how the polarity of molecules might impact our ability to smell the molecule.  Through the Lesson 45 PowerPoint, students learned that polar molecules are more likely to be detected by the nose as something with a scent although there are still polar molecules (like water) that do not smell.  We also visualized several molecules using a Java-based Molecule Polarity PhET simulation to give students a better sense of the concepts of electron density, bond dipoles, and molecule dipoles.  Emphasis was placed on the connection between bond electronegativity and overall molecule geometry.  During student work time, students cut out the molecules in the molecules handout and used the molecules to complete the Lesson 45 Worksheet.

Homework: