.png
)
Translations
| Code | Language | Translator | Run | |
|---|---|---|---|---|
 |
||||
Credits
Written by Loo Kang Wee; Felix J. Garcia Clemente; Francisco Esquembre; Designed by David Loh
1. Introduction:
This briefing document reviews two interconnected resources focused on teaching and learning covalent bonding through interactive "dot and cross" diagrams. The primary resource is a simulation tool designed to help students visualize and understand the sharing of electrons in covalent bonds. The second resource is a webpage hosting various interactive simulations, including one specifically for ammonia, and provides context, learning goals, teacher resources, and student feedback related to the use of these simulations.
2. Main Themes and Important Ideas:
2.1. Interactive Learning of Covalent Bonding:
- The central theme is the use of interactive JavaScript simulations to teach the abstract concept of covalent bonding. The simulations allow students to actively participate in creating dot and cross diagrams, providing a hands-on learning experience.
- The "O level Chemical Ammonia Covalent Bonding Dot and Cross Diagrams JavaScript Simulation Applet HTML5" page explicitly states its focus on "Chemical Bonding Dot and Cross Diagrams" and includes specific examples for various molecules and ions like hydrogen, chlorine, oxygen, nitrogen, hydrogen chloride, hydroxide ion, cyanide ion, water, carbon dioxide, nitrite ion, ammonia, methane, carbonate ion, and hydrogen peroxide.
- The simulations aim to move beyond passive learning methods like drawing diagrams on paper or viewing static representations. The student feedback strongly supports the idea that the interactive nature enhances engagement and understanding. One student noted, "The lesson was more hands on than just the teacher explaining to us how to draw dot and cross diagrams."
2.2. Pedagogical Approach and Learning Goals:
- The resources are designed for "O level" and "A Level" chemistry students, suggesting a target audience in secondary education.
- Sample learning goals mentioned on the "Ammonia Simulation" page include understanding "O level Chemical Bonding Dot and Cross Diagrams JavaScript Simulation Applet HTML5" and "A Level Chemical Bonding Dot and Cross Diagrams JavaScript Simulation Applet HTML5."
- The inclusion of "For Teachers" materials, linking to a Google Slides presentation, indicates that these simulations are intended to be integrated into classroom lessons. The request for feedback from teachers using the simulation in Singapore schools highlights a focus on pedagogical effectiveness and continuous improvement.
- The design encourages self-directed learning and immediate feedback. As one student commented, "The simulation allowed me to discover where the electrons should go and somehow, why it was like that." Another appreciated the ability to "trial and error so that I could figure out the bonding by myself."
2.3. Evidence of Effective Learning and Positive Student Reception:
- The "O level Chemical Ammonia Covalent Bonding Dot and Cross Diagrams JavaScript Simulation Applet HTML5" page explicitly mentions a positive student response based on surveys: "Our own survey suggests strong evidence on effective student learning, appreciative students, good simulation design."
- The extensive collection of student feedback provided on the page offers qualitative data supporting this claim. Students reported that the simulation:
- Helped them visualize concepts ("It was helpful to visualise the concepts.")
- Increased their interest ("It arouse my interest.")
- Facilitated independent learning ("can help me learn independently.")
- Made learning more interesting and engaging ("The simulation made the lesson more interesting as it was interactive.")
- Was easy to use and understand ("The simulation was easy to use and easy to understand.")
- Provided a clearer understanding of chemical bonding ("helps me to understand better about chemical bonding dot & cross diagram.")
- Offered a more efficient alternative to drawing ("The simulation is much easier than drawing the atoms out.")
- Allowed for easy correction of errors ("It was a lot easier to correct small errors using the simulation that it is with pen and paper.")
- Increased confidence in drawing dot and cross diagrams ("It was interesting and helped me to be more confident in dot and cross diagrams.")
2.4. Areas for Improvement and Ongoing Development:
- Student feedback also provided valuable insights into potential improvements for the simulations. Common suggestions included:
- Making the dragging and dropping of electrons less tedious ("Dragging and clicking of the electrons became tiring after a while... noted, We already designed a book icon that put all the electrons in appropriate positions, maybe need to tell students again?")
- Improving the ease of placing electrons ("it is slightly hard to drag the electrons and place them on their spots," "make it easier to drop the electrons.")
- Adding explanations for incorrect answers or hints used ("I would like there to be an explanation added in if the hint is used as seeing the answer alone does not help me understand the bond.")
- Providing more variety of compounds ("would it be possible to have a wider range of compounds that we can try to do?")
- Adding an undo button ("it would be nice if there was an undo button rather than completely erasing what you've done.")
- Improving the visual interface and adding more graphics ("more graphics can be added to make the site more interesting," "the simulation could be more colourful," "better interface design.")
- Labeling buttons clearly ("- labels for buttons. done")
- The developers have acknowledged some of this feedback, indicating ongoing development and a commitment to addressing user needs. For example, they noted increasing the sensitivity of the dragging area for electrons and plan to create a video tutorial.
2.5. Authorship and Licensing:
- Both resources credit Loo Kang Wee, Felix J. Garcia Clemente, Francisco Esquembre, and David Loh as the authors and designers.
- The "Covalent Bonding 'Dot and Cross' Simulation" explicitly states it is released under a "CC-BY-SA-NC" license, indicating it is a Creative Commons Attribution-ShareAlike-NonCommercial license. This allows for sharing and adaptation for non-commercial purposes with proper attribution.
- The "Open Educational Resources / Open Source Physics @ Singapore" branding highlights the commitment to freely available educational materials. The separate note regarding the commercial use of the "EasyJavaScriptSimulations Library" with a link to the license and contact information provides clarity on the terms of use for the underlying technology.
3. Key Facts and Quotes:
- Authorship: "Written by Loo Kang Wee; Felix J. Garcia Clemente; Francisco Esquembre; Designed by David Loh" (from both sources).
- Licensing: "© 2021, CC-BY-SA-NC." (from "Covalent Bonding 'Dot and Cross' Simulation"). "Contents are licensed Creative Commons Attribution-Share Alike 4.0 Singapore License." (from "O level Chemical Ammonia Covalent Bonding...").
- Positive Student Feedback: "Our own survey suggests strong evidence on effective student learning, appreciative students, good simulation design." (from "O level Chemical Ammonia Covalent Bonding...").
- Student Appreciation for Interactivity: "This is a more interesting style of learning" and "The simulation made the lesson more interesting as it was interactive" (from student feedback).
- Student Perception of Ease of Use: "The simulation was easy to use and easy to understand" (from student feedback).
- Desire for Explanations: "I would like there to be an explanation added in if the hint is used..." (from student feedback).
- Tediousness of Dragging: "Dragging and clicking of the electrons became tiring after a while..." (from student feedback).
- Developer Response: "...noted, Video Tutorial will be ready after march holidays." and "...noted i have increase the sensitivity to 50px..." (from developer responses to student feedback).
4. Conclusion:
The "Covalent Bonding 'Dot and Cross' Simulation" and the associated resources from Open Educational Resources / Open Source Physics @ Singapore provide valuable and engaging tools for teaching and learning about covalent bonding. The interactive nature of the simulations has been well-received by students, leading to improved understanding and increased interest in the topic. The detailed student feedback offers valuable insights for future improvements to enhance the user experience and pedagogical effectiveness further. The open licensing of the resources promotes accessibility and adaptation for educational purposes. These resources represent a positive example of leveraging technology to make abstract scientific concepts more concrete and accessible to learners
Covalent Bonding: A Study Guide
Key Concepts:
- Covalent Bond: A chemical bond that involves the sharing of electron pairs between atoms. These shared electron pairs are known as bonding pairs or shared pairs.
- Dot and Cross Diagrams: Visual representations of covalent bonding showing the valence electrons of participating atoms, using dots for one atom's electrons and crosses for another's. Shared electrons are shown in the overlapping region of the atoms' outermost shells.
- Valence Electrons: The electrons in the outermost electron shell of an atom, which are primarily involved in chemical bonding.
- Octet Rule: The tendency of atoms to prefer to have eight electrons in their valence shell. When atoms form covalent bonds, they share electrons to achieve a stable octet configuration (except for elements like hydrogen, which aims for a duet of two electrons).
- Duet Rule: The tendency of small atoms like hydrogen to achieve a stable configuration with two valence electrons.
- Molecule: A group of two or more atoms held together by chemical bonds, typically covalent bonds.
- Polyatomic Ion: An ion composed of two or more atoms covalently bonded or consisting of a metal complex that can be considered to be acting as a single unit. These ions carry an overall electric charge.
Quiz:
- Describe the fundamental principle behind covalent bonding. How does it differ from ionic bonding?
- What is the purpose of using "dots" and "crosses" in covalent bonding diagrams? Explain their significance in representing the bond formation.
- State the octet rule. Are there any common exceptions to this rule in covalent bonding, and if so, provide an example from the provided text.
- Explain how a hydrogen molecule (H₂) achieves stability through covalent bonding using the duet rule. Illustrate this with the number of shared electrons.
- For a chlorine molecule (Cl₂), how many valence electrons does each chlorine atom contribute to form a covalent bond, and what is the resulting electron configuration around each atom?
- In a nitrogen molecule (N₂), how many covalent bonds are formed between the two nitrogen atoms? How many electrons are shared in total?
- Describe the covalent bonding in a water molecule (H₂O). How many shared electron pairs are present, and what is the electron configuration around the oxygen atom?
- How does the dot and cross diagram for a hydroxide ion (OH⁻) differ from that of a neutral molecule like water? What accounts for this difference?
- Consider the carbonate ion (CO₃²⁻). Based on the description, what is unique about the electron distribution in this polyatomic ion's covalent bonds?
- Briefly explain how the interactive simulations described in the sources can enhance a student's understanding of covalent bonding compared to traditional methods like drawing on paper.
Answer Key:
- Covalent bonding involves the sharing of electron pairs between atoms to achieve a stable electron configuration, typically resembling a noble gas. Ionic bonding, in contrast, involves the complete transfer of electrons from one atom to another, resulting in the formation of oppositely charged ions that are then электростатически attracted.
- Dots and crosses are used to visually distinguish the valence electrons originating from each of the atoms participating in the covalent bond. This helps to track which electrons are being shared and ensures that the correct number of valence electrons from each atom are accounted for in the bond formation.
- The octet rule states that atoms tend to gain, lose, or share electrons in order to achieve a full valence shell with eight electrons. Hydrogen is a common exception, as it follows the duet rule, aiming for two electrons in its valence shell, as seen in the hydrogen molecule.
- A hydrogen atom has one valence electron. In a hydrogen molecule (H₂), two hydrogen atoms share their single valence electron, forming one covalent bond (one shared pair of electrons). This sharing allows each hydrogen atom to have two electrons in its outermost shell, satisfying the duet rule and achieving stability.
- Each chlorine atom has seven valence electrons. In a chlorine molecule (Cl₂), each chlorine atom shares one valence electron with the other, forming one covalent bond (one shared pair). This sharing results in each chlorine atom having eight electrons in its outermost shell (six of its own and two shared), satisfying the octet rule.
- In a nitrogen molecule (N₂), the two nitrogen atoms form a triple bond, meaning they share three pairs of electrons. Therefore, a total of six electrons are shared between the two nitrogen atoms, allowing each nitrogen atom to achieve a stable octet configuration.
- In a water molecule (H₂O), the oxygen atom shares one electron with each of the two hydrogen atoms, forming two single covalent bonds. There are two shared electron pairs. The oxygen atom has two of its own lone pairs and two shared pairs, resulting in a total of eight valence electrons around the oxygen, satisfying the octet rule, while each hydrogen has two (duet rule).
- The dot and cross diagram for a hydroxide ion (OH⁻) shows that oxygen and hydrogen share an electron pair, similar to a covalent bond in a neutral molecule. However, the hydroxide ion carries an overall negative charge, indicated by brackets and a "⁻" symbol. This negative charge signifies the presence of an extra electron, which is typically shown as belonging to the oxygen atom and contributes to its octet.
- In the carbonate ion (CO₃²⁻), the description indicates that one carbon atom shares four electrons (two pairs) with one oxygen atom, forming a double bond, while it shares two electrons (one pair) with each of the other two oxygen atoms, forming single bonds. The two oxygen atoms with single bonds each have a "foreign electron" in their personal shell, contributing to the overall 2⁻ charge of the ion, while all atoms achieve an octet.
- Interactive simulations provide a dynamic and visual way for students to manipulate electrons and observe the formation of covalent bonds in real-time. This hands-on approach, with immediate feedback, allows for active learning, trial and error, and a deeper understanding of the concepts compared to static drawings that require manual creation and teacher feedback.
Essay Format Questions:
- Discuss the importance of dot and cross diagrams in visualizing and understanding the formation of covalent bonds. How do these diagrams help to explain the stability of molecules?
- Compare and contrast the octet rule and the duet rule in the context of covalent bonding. Provide examples of molecules that adhere to each rule and discuss why these rules are essential for predicting molecular structure.
- Analyze the feedback provided by students on the "Covalent Bonding 'Dot and Cross' Simulation." Based on their comments, what are the key strengths of using such interactive tools for learning, and what suggestions do they offer for potential improvements?
- Explain how the concept of valence electrons is central to understanding covalent bonding. Discuss how the number of valence electrons in an atom determines the number and type of covalent bonds it can form.
- Considering the examples provided in the sources (e.g., hydrogen, chlorine, water, ammonia), discuss the variety of ways atoms can share electrons to achieve stable covalent bonds, including single, double, and triple bonds.
https://play.google.com/store/apps/details?id=com.ionicframework.covalentbonding this version has the valency question
Sample Learning Goals
- A Level Chemical Bonding Dot and Cross Diagrams JavaScript Simulation Applet HTML5
- O level Chemical Bonding Dot and Cross Diagrams JavaScript Simulation Applet HTML5
For Teachers
From Google slides (From David) to interactive https://docs.google.com/presentation/d/1fwutLc-jPc1fUyrxJsps3Fhg6_J9y8AEA4pHJ68gdBw/edit?ts=5dd2086a#slide=id.g5292a6c619_0_96
If you are using this simulation in Singapore Schools, please contact loh_jee_yong_david@mgs.sch.edu.sg to get a digital google survey form to collect anonymous data on the effectiveness of lesson and future imporvement to the simulation!. Thanks in advance.
Our own survey suggests strong evidence on effective student learning, appreciative students, good simulation design. Do you agree? let me know in the comments below! https://weelookang.blogspot.com/2020/02/o-level-chemical-bonding-dot-and-cross.html
Chemical Bonding Dot and Cross Diagrams
Polyatomic ions dot and cross diagram
|
|
|
Chemical Bonding Dot and Cross Diagrams for Hydrogen molecule |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Hydrogen molecule answer is add up to 2 on each H atom electron outermost with shared electrons = 2 |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Chlorine molecule |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Chlorine molecule answer is add up to 8 on each atom's' electron outermost shell with shared electrons = 2 |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Oxygen molecule |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Oxygen molecule answer is is add up to 8 on each atom's' electron outermost shell with shared electrons = 4 |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Nitrogen molecule |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Nitrogen molecule answer is is add up to 8 on each atom's' electron outermost shell with shared electrons = 6 |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Hydrogen Chloride molecule |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Hydrogen Chloride molecule answer is is add up to 8 on Cl atom and 2 for H atom and electron outermost shell with shared electrons = 2 |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Hydroxide ion |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Hydroxide ion answer is is add up to 8 on O atom and 2 for H atom and electron outermost shell with shared electrons = 2 |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Cyanide ion |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Cyanide ion answer is is add up to 8 on each atoms and electron outermost shell with shared electrons = 6 |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Water molecule |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Water molecule answer is is add up to 8 on O atom and 2 on H atoms and electron outermost shell with shared electrons = 2,2 respectively |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Carbon Dioxide molecule |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Carbon Dioxide molecule answer is is add up to 8 on each atom and electron outermost shell with shared electrons = 4,4 respectively |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Nitrite ion |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Nitrite ion answer is is add up to 8 on each atom and electron outermost shell with shared electrons = 2,4 respectively with the foreign electron on the O atom with the shared electrons=2 |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Nitrite ion answer is is add up to 8 on each atom and electron outermost shell with shared electrons = 2,4 respectively with the foreign electron on the O atom with the shared electrons=2 |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Ammonia molecule |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Ammonia molecule answer is is add up to 8 on N atom and 2 on H atom and the electron outermost shell with shared electrons = 2,2,2 respectively |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Methane molecule |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Methane molecule answer is is add up to 8 on C atom and 2 on H atom and the electron outermost shell with shared electrons = 2,2,2, respectively |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Carbonate ion |
|
|
|
Chemical Bonding Dot and Cross Diagrams for Carbonate ion answer is is add up to 8 on each atom and the electron outermost shell with shared electrons = 4,2,2, respectively. The two O atoms with 2 shared electrons has a foreign electron in it's personal shell. |
 |
|
Chemical Bonding Dot and Cross Diagrams for Hydrogen Peroxide |
 |
|
Chemical Bonding Dot and Cross Diagrams for Hydrogen Peroxide answer is is add up to 8 electrons on each O atom and 2 for H atom, the electron outermost shell with shared electrons = 2,2,2, respectively. |
Student Survey
survey 1 , 2 data from MGS 2020 total 1 + 2 classes estimated number of students (44 , 46) responses.
I have added some answers to the questions asked too.
 |
| typical classroom setting where the anonymous (photo blurred) teacher skillfully explains the learning tasks using https://sg.iwant2study.org/ospsg/index.php/922 |
 |
| typical classroom setting where the anonymous students are each working on their ChromeBook to learn by doing chemistry. this is far better than students working on Google Slides and trying to fit in the electrons on non simulation medium, only getting feedback on the accuracy after the teacher manually marked each students' assigned google slide prepared by the teacher. https://sg.iwant2study.org/ospsg/index.php/922 |
What do you like about the lesson? (For example, was the lesson successful in helping you to learn the concepts? In what way was the simulation helpful? Did it arouse your interest? Please give more details.)
- It was successful in helping me learn the basic concepts but it did not give me a very clear understanding of the concept. I was still left with questions and doubts. It was a unique and new way of learning in the classroom. noted, Video Tutorial will be ready after march holidays.
- Something new. No need to check the periodic table. There are other compounds not tested available. The emoji is cute.
- It was helpful to visualise the concepts.
- the lesson was successful in helping me to learn the concepts. the simulation was helpful. It arouse my interest.
- it is interesting and can help me learn independently.
- The lesson was more hands on than just the teacher explaining to us how to draw dot and cross diagrams
- This is a more interesting style of learning
- The simulation made the lesson more interesting as it was interactive
- the simulation was easy to use and easy to understand
- The simulation helps me to understand better about chemical bonding dot & cross diagram. I also can engage with the lesson better because we get to use technology during lessons and there are colours.
- yes,it helps me a lot ,I was confused about the definition yesterday night ,but through this lesson, I think I know better about the definition and the process .
- it helped me to understand better
- the simulation made me more interested in learning about chemical bonding.
- I like the fact that we got to learn through using our chromebook and got to try it out ourselves.
- it allowed me to understand more about the formation of covalent bonds
- I was fun and was an easier and more interesting way to learn about covalent bonding instead of literally drawing the atom over and over again.
- It keeps my interest because it is easy to use
- it was interesting i guess
- It was interesting and helped me to be more confident in dot and cross diagrams.
- that we get to attempt it ourselves first
- It is easy to use and informative
- it was easy to understand with answers and hints provided
- The simulation was cute and captured my attention so I enjoyed doing it.
- The simulation allowed me to discover where the electrons should go and somehow, why it was like that.
- it's easier to use
- it was easy and fun to use
- The lesson was successful in helping me learn the concepts. It gave me more practice in covalent bonding.
- the simulation gave me a concept of what covalent bonding is about
- The simulation is much easier than drawing the atoms out.
- I like that the lesson allowed me to learn independently and the diagrams were simple and easy to read.
- The lesson helped me have a clear visual on covalent bonding. Helped it to be clearer to me.
- The answers are not given on the first wrong attempt, we can continue to try to get to the correct answer.
- The simulation made the locations of the electrons clearer
- I like that it gives the number of electrons that the user has to use and that the user does not need to refer to the periodic table to do this simulation, increasing interest and ease in doing this while learning something.
- It was a refreshing change. Instead of drawing the diagrams on paper, I could move the electrons online.
- it is very entertaining and educative
- the visuals helped me!
- it was interesting
- The colour coding makes the visuals much more easier to see and understand the concepts.
- The lesson was very fun and engaging. The simulation allowed me to better understand the concepts.
- It was successful in helping me learn the concepts as it provided a solution and explanation when i didn't know how to do the question.There were also many question which allowed me to try out different questions or different levels of difficulty,allowing me to practice more.
- it was fun
- The hints especially helped me to understand the concept
- I can understand the structures more clearly. was quite fun to drag and drop instead of drawing for once. It's also much more convenient as i can check my work immediately instead of waiting for the teacher to come around
- The simulation was easy to use and was a good reference for doing the worksheet as well !
- the simulation was helpful in giving model answers for me to understand covalent bonding better
- The simulation helped me determine the number of valence electrons so it was easier to draw the dot and cross diagram. The simulation was very fun and easy to use and it was a drag and drop application
- was very successful
- the simulation helped me better understand the topic better and it was engaging
- I liked that it was more engaging and gave us room to think for ourselves while having some guidance from the simulation. The simulation made it easier to trial and error so that I could figure out the bonding by myself.
- it is interactive and clear:)
- It helped me understand the concept of bonding better. It was very interesting and helpful. I would like to do it again in class sometime.
- the lesson was easy to follow since the simulation was easy to use and we could just reset instead of redrawing
- It was a lot easier to correct small errors using the simulation that it is with pen and paper.
- It was pretty interactive and it helped us to apply important concepts when drawing dot-cross diagrams.
- - easy to use
- - I had more confidence in drawing dot and cross diagrams
- - wide range of ions to choose from
- - "hints" feature
- It was easy to use and a suitable amount of help was given (number of valence electrons per element were given)
- i liked how it was not too complicated to do the dot-and-cross diagrams and the website was easy to use.
- helpful - it prompted us and gave hints on how to draw the diagram
- yes i am interested
- it was good to check whether my diagrams were right
- Yes it was very helpful. I learnt how to draw polyatomic ions very quickly and I find this kind of simulation useful as I can self-learn without relying so much on the teacher. :)
- It gives a better visualisation of the dot and cross diagram and helps me to be able to draw the diagram easily.
- It made the process of thinking how to draw it much easier
- i was able to learn the concept faster with the use of the website
- It helped me visualise the covalent bonding between the molecules and made me curious to find out why the molecules bonded in a particular way
- I liked using the simulation to trial and error with the diagram and to fill in the worksheet.
- the platform made learning the dot cross diagram more interesting
- it helped me figure out the answer in my own.
- the lesson helped to make my understanding of covalent bonding clearer
- I liked the idea of figuring it out yourself and then having a check answer button this app is great!
- It made visualising the covalent bonds and the orientation of electrons easier.
- ー
- it is fun to drag the electrons around
- it gives me many chances for trial and error without having to continuously erase my mistakes
- I like that we get to explore the concept ourselves and learn by trial and error.
- The simulation was easy to use and allowed me to understand how to draw dot and cross diagrams as it told me what was wrong when I made a mistake
- I learnt how foreign electrons worked, and it was interesting to see try doing the different questions. It was also easier as the simulation already had the electrons shells put out for you.
- It helped me to visualise the concept better
- I liked the lesson because it was more engaging and hands-on, and it also helped me to learn the concepts. It is also better than having to draw out a dot and cross diagram myself.
- It helped me to see the chemical bonds visually which was very helpful
- It allowed me to easily move each electron around before writing it on my paper thus it was easier and neater. Furthermore, because of the difference colours it is easier to see the electrons
- The simulation made it easier for me to visualise the atoms, aiding me in figuring out the configuration of different compounds.
- It was successful in conveying the concepts of chemical bonding. It allowed me to explore the concept better.
- It allowed me to understand the concept better as it gave an explanation when providing the answer which was more comprehensive then just searching for the answer online.
- it was interactive and helped me to understand the lesson better
- I think it helps me understand where I went wrong and teaches me how to correct my mistakes before I write it down and have to go through the trouble of changing it over again and again.
- it was fun and easy to use!
- kept me engaged and aroused my interest
- it was successful because it was fun and interesting
In what way can the lesson or the simulation be improved? (For example, what features in the simulation would you like to change or add?)
- NIL
- Dragging and clicking of the electrons became tiring after a while, and it was very repetitive and could be more engaging. noted, We already designed a book icon that put all the electrons in appropriate positions, maybe need to tell students again?
- An option to include non-valence shells and a box of different colours of ions(we choose how many to take) but include the periodic table at the side.More effects and colours so it will be more attractive. If you can, thank you! noted, while the idea has merits, it may be too difficult when there is a unknown number electrons to position on the atomic shell, so it is unlikely i will implement that idea.
- It is a bit hard to drag the dots and crosses to their respective molecule. noted i have increase the sensitivity to 50px, meaning the dragging area is now 50x50px on the electrons O and X.
- the simulation can have more.
- -nil-
- We can only place the dots and crosses at certain places of the ring
- add a function that could help memorise the formulas or dot and cross diagrams better
- I think it is already very good.
- figure out how to make those who do not have touch screen laptop use more easily
- -
- it is slightly hard to drag the electrons and place them on their spots
- more graphics can be added to make the site more interesting.
- -
- Harder questions.
- Make the colours of the molecules in the simulation brighter as some were dull and
- i feel that the moving of dots was quite tiring and tedious
- The lesson can have more of these interactive games to keep us engaged.
- instead of drag and drop change it to click to grab and click to drop
- the simulation should have a function that allows us to pull all the electrons to the outer circle so we do not have to do it one by one.
- I would like there to be an explanation added in if the hint is used as seeing the answer alone does not help me understand the bond.
- make it easier to drop the electrons
- There can be some pop ups where the user can see what that compound is applied in daily lives so to spark more interest in learning these compounds:))
- it could be more aesthetically pleasing
- the toggle was a bit weird
- the electrons can be larger so it's easier to drag.
- NIL
- I think the thinking emoji can be changed to something like "Check" because some people didn't really know what to press to check the answer immediately. noted, i have added text check hint and reset.
- I find it tedious to move every single subatomic particle to its spot! I'd rather have them assigned to their respective atom and then move them around from there !
- make it more appealing including the colour lilac
- Instead of dragging the ‘x’ or the ‘o’ , we can tap them to move them from one place to another.
- there could be an explanation for why some ions are bonded that way
- nil
- - labels for buttons. done
- - better interface design
- Just select directly on the diagram instead of dragging it as it is quite tedious without touch screen.
- explanations should be given when students gets the answer incorrect.
- how to derive the answer
- Easier dragging of electrons cause sometimes it lags.
- More explanation (rgd concepts) please! Thank you! (esp for the last few qns)
- make it easier to drag and drop the electrons?
- There can be an explanation for the bonding after students submit each answer.
- would it be possible to have a wider range of compounds that we can try to do?
- it would be nice if there was an undo button rather than completely erasing what you've done, also its a bit tedious having to drag things over it may be nice if you can select an electron and place it in a spot
- pop up tutorial of how to use it. I wasn't really sure about how to check my answers. video coming
- more variety of compounds
- more graphics?
- The simulation could have a one step 'backspace' key instead of a total reset so we can undo step by step and do not have to reset when we want to backtrack.
- The simulation is really good and there is no improvements that I would want to see made.
- more covalent bonds/questions as the range of selection is small right now
- label the buttons as some students were confused on how to check the answer noted
- The simulation is a bit laggy.
- I think the explanations as to why our answers were wrong can be clearer as I was a bit confused when it first came out and didn't really understand what to do.
- the simulation could be more colourful
- automatically go on to the next qn
Any other feedback or comments for your teacher or the simulation designer? (This question allows students to feedback on any other matters. For example, you could thank your teacher or say how you feel about this simple technology enhanced lesson.)
- NIL
- -
- This app is really interesting. Thank you for spending time to make this app!
- it is fun
- -nil-
- I think the teacher should explain it more clearly first because I actually don't understand it before having to explore the simulation. I feel appreciative that the simulation designer designed this thing that helped me to understand more about the topic.
- quite great
- -
- Using technology during lessons is more fun. :)
- :D
- The simulation was really cool! Thank you so much!
- Thank you Ms T for giving us time to try out this simulation and allowing us to learn on our own! :)
- The simulation is much faster and more efficient than physically drawing covalent bonds.
- Thank you for the lesson!
- nil
- This simulation is a really great way to get students to practise and they can see how to draw and where to put the electrons in the correct places!!
- it is quite hard to drag the electron , noted sensitivity set to 50 px
- thank you for the lesson
- thanks haha:))
- NIL
- Thank you Ms T for trusting us to do our own self- learning ! Despite you not actively teaching us, it was a simple but fruitful, hands-on lesson ^-^
- thank you v much heehee
- -
- -
- thank you for the website
- THANk You MS C T
- i enjoyed the lesson using the simulation very much! thank you!
- thanks
- Thank you for letting us use this simulation.
- It's really good :)
- Thank you for creating this!
- Thank you for spending so much time and effort to create this simulation make our lessons more interesting!
- This lesson was very fun! Thank you for making the simulation!!
- thank you for this simulation. it was simple but effective
- thank you for making this programme !
- Would it be possible to have the electrons of the atoms to be an option to click on before filling in the configuration,so we don't have to drag the ones given to their rightful place?
- I like this.
- N/A
- it was really fun!!!
Video
Version:
- https://weelookang.blogspot.com/2019/12/chemical-bonding-dot-and-cross-diagrams.html
- https://sites.google.com/a/mgs.sch.edu.sg/about-me-david-loh/
- https://weelookang.blogspot.com/2021/09/o-level-chemical-ammonia-and-methane.html
Other Resources
[text]
Frequently Asked Questions: Covalent Bonding Simulations
1. What is the purpose of the "Dot and Cross" simulation for covalent bonding? The primary purpose of the "Dot and Cross" simulation is to provide an interactive and visual tool for students to understand the formation of covalent bonds in various molecules and polyatomic ions. It allows users to manipulate electrons (represented as dots and crosses) to show how atoms share electrons to achieve a stable electron configuration, typically a full outer shell (duet rule for hydrogen, octet rule for other elements). This hands-on approach aims to enhance learning and make the abstract concept of covalent bonding more tangible and understandable.
2. How does the simulation help students learn about covalent bonding? The simulation aids learning by allowing students to actively construct dot and cross diagrams for different chemical species. This "learning by doing" approach is more engaging than passively viewing static diagrams. The simulation often provides feedback (implicitly by allowing correct arrangements and requiring adjustments for incorrect ones), hints (like the number of valence electrons), and model answers, enabling students to self-correct and deepen their understanding. Many student testimonials highlight that the simulation makes the concept easier to visualize, more interesting, and helps them learn independently and with more confidence.
3. Which chemical species are typically covered in these "Dot and Cross" simulations? Based on the provided text, the simulations cover a range of common molecules and polyatomic ions exhibiting covalent bonding. Examples explicitly mentioned include hydrogen (H₂), chlorine (Cl₂), oxygen (O₂), nitrogen (N₂), hydrogen chloride (HCl), hydroxide ion (OH⁻), cyanide ion (CN⁻), water (H₂O), carbon dioxide (CO₂), nitrite ion (NO₂⁻), ammonia (NH₃), methane (CH₄), carbonate ion (CO₃²⁻), and hydrogen peroxide (H₂O₂). This suggests a focus on fundamental examples relevant to O Level and A Level chemistry curricula.
4. Who developed these "Dot and Cross" simulations and what is the licensing? These simulations were written by Loo Kang Wee, Felix J. Garcia Clemente, and Francisco Esquembre, with the design attributed to David Loh. The simulations are typically © 2021 and released under a Creative Commons Attribution-Share Alike-Non-Commercial (CC-BY-SA-NC) license. This licensing allows for the free use and sharing of the resource for non-commercial purposes, provided proper attribution is given and any adaptations are shared under the same license. The underlying simulation engine is often EJS (Easy Java/JavaScript Simulations) Toolkit.
5. What are some reported benefits of using these simulations in the classroom? Surveys and student feedback suggest several benefits. These include more effective student learning, increased student engagement and interest, better visualization of abstract concepts, opportunities for independent learning and self-correction, immediate feedback compared to traditional methods like manual marking of drawings, and a more hands-on learning experience. Students also appreciate the ease of use, the ability to try different arrangements without the need for repeated drawing and erasing, and the provision of hints and answers.
6. What are some suggested improvements or desired features for the simulations based on user feedback? User feedback indicates several areas for potential improvement. Common suggestions include making the dragging and dropping of electrons less tedious (especially for non-touchscreen devices), adding explanations for incorrect answers or the bonding process, increasing the variety of compounds available in the simulation, providing an "undo" function, improving the visual aesthetics, and potentially incorporating real-world applications of the compounds being studied to enhance interest. Some users also requested features like the ability to move all valence electrons at once or to select electrons directly on the diagram.
7. Are these simulations being used in Singapore schools, and is there any data on their effectiveness? Yes, the text explicitly mentions the use of these simulations in Singapore schools, particularly referencing Methodist Girls' School (MGS). There is also a call for Singaporean teachers using the simulation to contact the developers to participate in data collection on lesson effectiveness. The developers' own survey data is cited as providing "strong evidence on effective student learning, appreciative students, good simulation design." This suggests an ongoing effort to evaluate and improve the educational impact of the simulations.
8. Where can these "Dot and Cross" simulations be accessed and potentially embedded? The text provides direct links to various "Dot and Cross" diagram simulations for specific molecules and ions, typically hosted on the "Open Educational Resources / Open Source Physics @ Singapore" platform (sg.iwant2study.org). Furthermore, an embed code (iframe) is provided for the Ammonia molecule simulation, indicating that these interactive models can be easily integrated into other webpages or learning management systems, facilitating wider accessibility and use in educational settings.
- Details
- Written by David Loh
- Parent Category: Chemistry
- Category: 03 Chemistry of Reactions
- Hits: 4200