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The justification document is here!


link to the actual document is here (pdf)


The users of these lessons are high school chemistry students. I assume my users do not know anything about chemistry but they are in a course to learn about it. They are at least fourteen years old. For words like intermolecular forces and polarity, I would expect the students of my curriculum to at least be tenth grade chemistry students. I expect them to have at least a fifth grade reading level.
Before this unit students should know what atoms are and the parts that make up atoms. They could have learned it in the previous unit- it is not like this unit is for a 2nd year chemistry class. This unit is for regular students, but they should already be familiar with atoms having electrons that can be added or removed. They don’t have to know the rules for why atoms gain or lose electrons because that will be covered in this unit.
I assume my users know what elements are, what electrons are, what it means to gain or lose an electron, and what it means to share electrons. I assume they have access to a periodic table that lists electronegative values or a list of elements and their electronegative values.

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Why I think the images will work (Graphic Description):

Four word images:

Of the four words I chose, three became quite useful in the website. I turned “ionic bonds”, “covalent molecules”, and “intermolecular forces” into banners for their respective sections. The banner for each main lesson section is an adaptation of the image I made for class. I repeated the image and aligned the repeats to make it look like the banner is a continuous flow of information.  For the first page, the “home” page,  and for the landing pages for the lesson plans, unit plan, and justification paper, I created a different banner that has hotspot links to the three main sections.  
The inspiration for the images, the font styles, and arrangement came from chapter 9 of our text. I used these images in a non-serious place to add something more amusing than the content-laden text on the webpages. They are intended to accent the content, not be the content. Chapter 10 in Lohr’s book gave us ideas on how to use images to accent content instead of merely being the content.

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What is good about the four word images:

Ionic bonds- show two similarly shaped objects being near each other, each one having a charge. This emphasizes ionic bonds involve charged ions.
Covalent molecules- are hooked with a lock. This is because the atoms in covalent molcules are linked together by sharing electrons. The lock is to emphasize the permanence of covalent bonds.
Intermolecular forces- the fuzzy stuff between the parallel words is supposed to represent some forces that are connecting the words.
Polarity- the image shows how one side of the word can be partially positive while the other side of the word is partially negative. It turns out that I did not address polarity as a formal part of the instruction in the covalent bond lessons so the revision to this image is not among the lessons online, yet.

Shape tools: Ionic bonded crystal


User supplement:

My users are high school chemistry students. I assume they will be inquisitive and will want to know why the heck they are being given an image like this to look at. I am hoping that on their own they will notice:

If they do not notice this on their own, then the lesson will be written that asks them questions that should lead to these conclusions.

Components utilized that featured that week’s objectives, Shape Tools:

Facilitate comparisons, p. 252:  Using two different ions each with its own color scheme.  The green one gets smaller, the blue one gets larger. In their transformed sizes, they align in rows, alternating shapes.
Simple shapes, p. 250: These are simple circles used to represent the size of atoms and ions. They are deliberately colored so they look complex, but the overall shape is very simple. The image gets bigger or smaller depending on if it gained or if it lost an electron.

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Typography: Electronegativity chart


User update:

They do not need to already be familiar with electronegativity. This image could be used during the lesson on electronegativity, but they need to already have an idea that atoms have a desire for electrons.

There were several things that I paid attention to while designing this image:

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ACE: HONC1234 image



User update:

Before they use this image they should know the definition of a covalent bond- it is a bond where two or more atoms share electrons to create the bond. Ideally they will have learned this in the ionic bond set of lessons if they did not know it before taking the class. Students need to know what valence electrons are – the ones in the outermost layer of the atom that are involved with covalent bonding or the ones that are lost when becoming an ion. They also need to know that the magic number of valence electrons is 8, except for Hydrogen which is stable with 2. The majority of atoms are most stable when they have 8 electrons in their valence shell or layer. If they have done Lewis Dot diagrams before, they will be more comfortable with the images. If they do not know what valence electrons are before this lesson, they will after we’re done.

Why I think it will work:

The point of this image is for students to see why certain atoms tend to bond a specific number of times. There is a mnemonic HONC - 1234 which some of us use to help guide us when drawing molecules or with figuring out formulas.  I start out the image on the left with a Lewis Dot picture of a few atoms.  The next column emphasizes where they have “gaps”. The gaps are spaces that will be filled by electrons from other atoms. The third column shows how Hydrogen can bond with the other atoms because it brings one electron with it to fill the gap. Then they see how this image turns into a molecular formula. HONC - 1234 does not include a halogen unless you want to think of the H also being halogen for having one spot to bond. I included an example of a halogen so they could do the guessing exercise at the bottom. I wanted to include a formative assessment- a way for them to see if they get it. I put the answer key with the image so they can check their answers right away.

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Components utilized that featured that week’s objectives, ACE, Analyze, Create, Evaluate:

I did not break down the process of creating this image to necessarily use the ACE methodology. When I created the image, I thought of how I used to teach this concept in person. How did I get students to see why two atoms would be able to share electrons and also why would they bother?
There are several components to the chart because at first it appears to be a way to organize word-based content. After all, the symbols for elements are letters. Looking at the symbols, we see that there are two ways they are being represented. First you see them in their Lewis Dot structure- the way the symbol is drawn showing valence electrons. Then I expanded that idea by showing the gaps. The gaps are not normally drawn while learning about valence electrons. They are not a part of Lewis Dot diagrams.
I think the most influential part of the chapter was the PAT part starting on page 80. I was trying to keep the image as clean and as simple as possible while including all of the pertinent information. I could have left out the column showing the gaps, but based on prior experiences with students, leaving out that part would not help them. I’d just end out with questions like, “What do you mean by gaps?” By including a column of gaps, I am anticipating student confusion and am trying to circumvent it.  With the tools, page 85, I chose consistency with a color scheme, repetition of the symbols in the columns being in the same order and just changing a feature from one column to the next, using circles to represent gaps, and using stars to represent electrons- the performers of the bonding act.

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CARP images: Tetrahedral, Trigonal Pyramidal, and Bent



User update:

The users are students in a high school chemistry class. Before they use this image they should know the definition of a covalent bond- it is a bond where two or more atoms share electrons to create the bond. Students also need to know what lone pairs of electrons are- that they are just electrons that occupy a space but don't really have any matter to them. They have a negative charge which repels the other, bonded, atoms away from the lone pair of electrons. If they are familiar with geometric shapes, then this will play on their prior knowledge, but it is possible to teach this without students knowing what tetrahedral, pyramidal, or bent shapes are. Knowing that tetra means 4 helps them learn the name of the shape, but most students don’t think in three dimensions yet so tetrahedrals don’t have much meaning. Students are familiar with pyramids, but most pyramids have a four point base. In chemistry we teach them that the word “trigonal” has to go with pyramidal because it has a three point base. Pyramidal is significant because students would otherwise expect the central atom and the three bonded atoms to be in the same plane. The lone pair of electrons forces the bonded atoms out of the plane to make a slightly pyramidal shape.

Why I think it will work:

If students are not in a classroom where they can handle molecules from a kit, then these images will at least let them see what a picture of a three dimensional molecule looks like. The images themselves, explain one way of how to draw in three dimensions. All of the basic information about the molecules and why they have the shape they have is included with the image. They are designed to be a set and will not have as much meaning alone. NOTE: the images linked here are full page images just in case the reader needs a reminder of what the images were. I split the images into two halves in the website so the parts of each image would be easier to see.

How CARP is considered in the image:


I do not know if I excluded enough. I tried to put the explanation part in a way that it could be skipped if students want to ignore it. The main parts are in short segments and are spaced (aligned) so that they can stand on their own.


I tried to chunk this as much as possible. The 2-D part has its own space. The 3-D part has its own space, as do the explanations, the geometric figures, and the pictures from the model kits. In the revision, I felt like I had the freedom to use as much space as made sense so I made this bigger to take advantage of white space while splitting the images into two parts to take advantage of linking larger versions of the image to a big thumbnail in the website.


The original image was conceived with the idea of repeating the original molecule with a central atom and four atoms bonded to it. That is actually how I teach the shapes. We start with the tetrahedral model and remove bonded atoms. The lone pairs can actually exert more force than the bonded atom, so as we remove the bonded atoms, the ones that remain are actually squished together a little bit more. That movement is so small that we don’t worry about it. The molecules other than the tetrahedral one are copies of the tetrahedron without one or two of the bonded atoms. It is repetitive by nature. In the first image which I decided to not continue was going to be a repetitive showing of the 2-D image, the 3-D image, the hand drawn geometric shape, and there was going to be a fourth column of photographs of the molecules built with a 3-D kit. I may still go back to add that to the original idea, but I did not keep up with the formatting of the first image once I realized I needed to split it into individual images for each shape.


I labeled the atoms in the images as clearly as possible. The central atom label improved upon revision. Proximity was used with labeling all of the images, titling the sections, and keeping like terms or concepts together.

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Selection: Receptor binding to its ligand

(part 1, part 2, part 3)

I totally blew it on this one. The image I was trying to go for was showing a toxin binding to the receptor. I completely discarded the image I made for class and am substituting another quickly hand-drawn image in its place. The hand drawn image is done with digi-pencil an app for my iPad. I am not sure what design principles were formally being used by my goal was to create a simple image that did not have any clutter. My original image had too much clutter that interfered with the point I was trying to make. Actually I did an image in Fireworks/Illustrator to try to capture the idea that atoms are involved in the actual “bonding” that happens, but that image was also too messy, had too many colors and too much activity going on. That image may have made it to the website I made while I was posting things for class, but it did not make it to the final project website.

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Color part 1: molecules binding to receptors in the nose

(old_image, pie_nose image, inside_nose)

This is the other image that was not very successful. I was trying to do the three dimensional type of picture where you see something happening and there is a blow-up of the focal part of the image. Blow-up is what this image sort-of did. I was using color to represent molecules, trying to represent the interior surface of the nose, and using a black void to represent the molecules that don’t get stuck are able to travel on. A couple things I am proud of with the image is the person’s face. I actually communicated this was a face by only having eyes, a nose, a silly grin and a few sprigs of hair. There is no outline of the head which has me very excited because it took me a long time to figure out how to make a face that had dimension without messing it up by having an outline of the head.  I tried drawing silhouettes so I could emphasize the nose. Those were messy. I kept messing up the chin and back of the head. Since those side view pictures were not working, I went for the front view with a big nose. This image was drawn in Fireworks or Illustrator. I had not found the digi-pencil app yet. The second part I am proud of are the molecules being somewhat accurate. The molecule that gets stuck on the nose is an ester. Esters smell sweet. It might be possible for a student taking the class to realize the molecule sticking is an ester which would make me, the teacher, very happy. For students to recognize the nitrogen, oxygen, and water molecules continue up the nose and don’t stick would be fantastic. If a student did not spontaneously recognize what stuck and did not stick, then I’d ask them to see if they notice anything interesting about the image. The rest of what works (or does not work) is in the next section- the attempted revisions.

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Color part 2: Functional groups and how they smell

(sweet, putrid, fishy, camphor, minty)

The last image emphasizes functional groups and what we think when the molecules containing them land in our noses. Each functional group has its name, an image that suggests what we can think of when we experience the smell or the origin of the molecules that cause the smell, and an example of a molecule that causes us to perceive that odor. The first image was one really long strip of information. I’ll explain the revisions in the next part.
To create the image, I drew the color pictures in digi-pencil. At some point during the semester I downloaded several apps anticipating I may be able to use them to communicate to my computer with the iPad as a tablet or be able to use the iPad as a drawing tablet. I did download an app that should let me use the iPad as a remote device, but I could not get it to work the way I envisioned so I still do not have a tablet for my computer. I was successful, however, in downloading at least one app that let me draw images that have the outline be one color and the interior of the shape be another. For the most part, I just used the same color for the image and its outline, probably because I did not figure out the contrasting abilities of the app until I used it to redraw the ligand-receptor images. For this image I concentrated on the width of the pen options and smoothing out edges with the eraser. Using my fingers on the iPad was infinitely easier than using them on my tiny touchpad on my laptop. Plus this touchpad is disappointingly frustrating so using an object that responds well made it even more fun to do the images for this assignment.
Information about the molecules or their source came from the Internet. My knowledge about smells came from teaching the Smells unit in the Living by Chemistry curriculum.

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Design Process and changes made based on peer feedback:

Four words:

For the final ionic bond header, I put in lots of + and – symbols to emphasize the idea of ionic bonds relying on opposite charges.
I modified the covalent moleules image after it was posted to the class’s website to make the bonding with the lock more obvious.
For the actual website, I used the idea of “Look Engaging”, (Lohr p. 254), to add some festivity to the webpages.

Ionic crystal

I completely redid the ionic crystal because it was too two dimensional. I don’t think the idea that the ions are related to each other was really communicated in the first version. Plus, it did not make much sense having a negative ion atop of a negative ion. My rows of ions were not well done in the first image.
I added lines to emphasize a 3D structure to the crystal and to give it some depth. I also used lines to illustrate a connection from one ion to another one. Chapter 10 does not emphasize depth, but it mentions providing direction on page 254 and motion and direction on p. 253. In a way, the 3D scaffolding is showing a direction to the way the ions are aligned.
I put in words for the + and – like Dr. Hsu recommended. So that it would be more clear that electrons were being gained or lost, I used words and not just symbols.

Electronegativity chart:

Based on peer feedback I put a border around the two parts that make up the main chart. I am still undecided whether or not I like having borders around each of the smaller chunks of the table. I don’t know if the frames around the sub-tables serves to clarify there are two main parts to the big table or if it is merely chartjunk (Lohr, p. 139.)

HONC1234 Image:

Dr. Hsu pointed out that the electrons on Chlorine were not correct so I fixed them. I also added a statement explaining why we include halogens with these examples.

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CARP images: Tetrahedral, Trigonal Pyramidal, and Bent

These images underwent several transitions and changes. Ultimately they were broken down into two parts so that they could be more easily seen on the website used for the final project. The goal for the final project’s website was to make the images essentially be large thumbnails so readers could get a general idea of what the image is. If they want to see it bigger, they would click on the image and it opens up in a new tab. I felt I had to do this because of the size of laptop screens now-a-days and because a really big or a really long image is not inviting to viewers.
Based on peer feedback I made the central atom’s shape larger so you can actually read the words, “central atom”.
I removed some of the redundant or unnecessary text. I aligned general descriptive text at the top. I tried to have some uniformity among the three main images so that they could be seen as a set that have common features.
At the website, each image has its own page and people can easily flip from one to another. This is intended to not overwhelm the viewer with too many images concentrated in one place.
The progression of this image went from:

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Selection: Receptor binding to its ligand

I discarded the original image and replaced it with three simplified images. The first one is supposed to show how a big molecule can bind to a smaller one. The importance of the molecules being able to fit, one partially inside the other, is what I hoped to communicate. That concept was lost the first time I made an image for this teaching purpose. The second image emphasizes the active site, or where the ligand binds to the receptor. In this image I give examples of why these two molecules can connect. Once again, my goal is to simplify what I’m trying to communicate. The orange and blue colors are just a coincidence they are also Boise State colors. The color palate of digi-pencil is quite limited. The third image is to emphasize that the binding of the toxin or ligand molecule to the host protein or receptor molecule can cause a change in the receptor protein’s structure. Here I am trying to communicate in very simple terms that when toxins bind to host proteins, they can cause changes. I will let the reader make assumptions or guesses as to what those changes can be. I had too much science in the first image I tried to use to communicate this idea so in this set of three images I really wanted to cut out the science and focus on the main ideas. Small molecules can bind to big ones via intermolecular forces and when they bind, the complex’s shape can change.

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Color part 1: molecules binding to receptors in the nose

The first suggestion that I heard from most people was to show the smell molecule coming from something giving off an odor. Pete, my husband, tried to convince me it was “easy”. Sure, maybe it is easy to communicate the idea, but imagining how to draw a pie that had molecule escaping was not intuitive for me. Thus, my pie image is incredibly simple- it does not have the cuts in the crust like I imagine when I think of pies. There is a severe lack of detail which will probably serve as an asset. To show this part, I made small copies of the ester and had it “float” out of the pie and up to the nose. On the revision, the esters don’t look completely like ants, but wow, they sure do on the shrunken image I made for the project’s website. The large thumbnail looks like there are ants crawling up the nose.  In addition to adding the pie with the migrating esters, I added some explanatory words to what was going on. I spelled out what I was trying to show with the ester sticking on the side of the interior of the nose, and the small molecules floating in the black space. One other correction I made was to turn the solid brown lines into dashed lines to emphasize this is a blown-up image of what is in the nose.
The image is still not good. I chose to further improve other images for the final project because my brain was able to change those other images so they made sense. If you notice the image put up at the website is different than what is described here, then that means I was able to conceive of a way to change the image so it communicated what I want it to say. I may chop out the blow-up of the inside of the nose and split this into two separate images- the idea that smell molecules go up to the nose and therefore we recognize the sweet smell. If I can imagine and create a better interior surface for the nose while communicating that not everything sticks, I’d be elated. At the moment I am not confident I can create the molecule sticking image. Addendum, May 3: I did split the image so the pie and face are on one image. The inside of the nose requires some imagination for it to make sense. What I did do intentionally is try to have some perspective where the nose extends from the foreground backwards. It is supposed to represent air molecules travelling into the nose and toward the lungs. There are lines outlining the molecules that stuck. These are supposed to be just slightly larger than the molecule to show that the molecules fit snugly with their receptor molecules.

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Color part 2: functional groups and how they smell

Dr. Hsu and others suggested I use more whitespace to offset the large “pictures” with the molecules and text so first I rearranged some of the parts in the image. I swapped sides with molecule and representation of real-life image for a few of the smells. That image did look better, but it was still really long and cumbersome. At about this time I was on my pursuit to make large thumbnails that when clicked, open up a larger image in a new tab or window. That is when I realized I could not only split this image into several smaller ones, but I could integrate them with the text I was writing for the lesson that goes with the images. So now the ester is with the description of esters and their smell. The fishy is with the explanation of amines. The putrid is with the carboxylic acids and ketone is with minty and camphor. Alcohols can smell lots of different ways and since they are more complicated, I did not go crazy with matching them to an image.
Chunking up the smells allows each one to be seen as its own image, which clarifies what the reader is supposed to look at.

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Castro, Elizabeth. (2007) HTML, XHTML &CSS: Learn HTML, XHTML, and CSS the Quick and Easy Way. Berkeley, California: Peachpit Press.

Jmol: an open-source Java viewer for chemical structures in 3D. retrieved from

Lohr, Linda L. (2008) Creating Graphics for Learning and Performance: Lessons in Visual Literacy. Upper Saddle River, New Jersey: Pearson.

RCSB Protein data bank (2012) retrieved from:

Stacey, Angelica M. (2012). Living by Chemistry. New York, New York: W.H. Freeman & Co.

Tufte, Edward R. (1997). Visual Explanations: Images and Quantities, Evidence and Narrative. Chelshire, Connecticut: Graphics Press.

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Various online references were used for images or detailed information about molecules. These references include:

Image inspiration for Eucalyptus leaves retrieved from Retrieval date: April 14, 2012.

Image inspiration for Minty leaves retrieved from Retrieval date: April 14, 2012.

Information about piperitone as a minty molecule retrieved from Retrieval date: April 14, 2012

Fishy smelling molecule retrieved from Retrieval date: April 14, 2012.

Names for chemical molecules retrieved from Retrieval date: April 14, 2012.

Image for propyl butyrate retrieved from Retrieval date: April 14, 2012.

Camphor Tree information retrieved from Retrieval date: April 14, 2012.

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