Translations

Code	Language		Translator	Run

Credits

Written by Loo Kang Wee; Felix J. Garcia Clemente; Francisco Esquembre; Designed by David Loh

Authors/Designers: Loo Kang Wee, Felix J. Garcia Clemente, Francisco Esquembre (Writers); David Loh (Designer)

Copyright/License: © 2020, CC-BY-SA-NC. Compiled with EJS 6.0. Released under a license (likely the Creative Commons Attribution-Share Alike Non-Commercial license). Commercial use of the EasyJavaScriptSimulations Library requires a separate license from fem@um.es.

Main Themes and Important Ideas/Facts:

This briefing document reviews an interactive simulation tool designed to help students learn and visualize covalent bonding using 'dot and cross' diagrams. The primary focus is on the simulation's features, learning goals, pedagogical benefits, and student feedback.

1. Nature and Purpose of the Simulation:

• The core of the reviewed material is a JavaScript/HTML5 simulation applet focused on drawing dot and cross diagrams for covalent bonding. It appears to be available as an embeddable model for webpages and potentially as a mobile app ("this version has the valency question" referring to a Google Play Store app).
• The simulation aims to provide an interactive and visual way for students to understand how atoms share electrons to achieve a stable electron configuration (typically following the octet rule, or duet rule for hydrogen).
• It includes various examples, ranging from simple molecules like hydrogen and chlorine to more complex ones like water, carbon dioxide, and polyatomic ions such as hydroxide, cyanide, nitrite, and carbonate.
• The simulation explicitly incorporates valency options, suggesting that students can explore different bonding possibilities.

2. Sample Learning Goals:

• The resource explicitly states sample learning goals for "A Level Chemical Bonding Dot and Cross Diagrams JavaScript Simulation Applet HTML5" and "O level Chemical Bonding Dot and Cross Diagrams JavaScript Simulation Applet HTML5," indicating its suitability for different educational levels.

3. Features and Functionality:

• The simulation allows users to manipulate electrons (represented as dots and crosses, presumably to distinguish electrons from different atoms) to form covalent bonds.
• It provides feedback on the correctness of the drawn diagrams, as suggested by the student feedback mentioning "answers and hints provided" and the ability to "check whether my diagrams were right."
• The simulation appears to provide the number of valence electrons for each element, reducing the need for students to constantly refer to the periodic table ("No need to check the periodic table. There are other compounds not tested available.").
• A "reset" button is available to allow users to restart their attempts. A "check" function is also present ("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.").
• There is a "hints" feature that assists students in understanding the concept.

4. Pedagogical Benefits and Effectiveness:

• The materials emphasize the benefits of using this simulation in the classroom, contrasting it with traditional methods like drawing on paper or using static Google Slides ("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.").
• A student survey conducted in Singapore schools suggests "strong evidence on effective student learning, appreciative students, good simulation design."
• Student feedback highlights several positive aspects:
• Visualization: "It was helpful to visualise the concepts." "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." "The simulation made the locations of the electrons clearer."
• Engagement and Interest: "It arouse my interest." "The simulation made the lesson more interesting as it was interactive." "The simulation was cute and captured my attention so I enjoyed doing it." "It keeps my interest because it is easy to use."
• Active Learning and Independence: "The lesson was more hands on than just the teacher explaining to us how to draw dot and cross diagrams." "it can help me learn independently." "It allowed me to understand more about the formation of covalent bonds." "It allowed me to discover where the electrons should go and somehow, why it was like that." "I like that the lesson allowed me to learn independently and the diagrams were simple and easy to read." "I liked the idea of figuring it out yourself and then having a check answer button this app is great!"
• Ease of Use and Efficiency: "the simulation was easy to use and easy to understand." "The simulation is much easier than drawing the atoms out." "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."
• Immediate Feedback and Trial-and-Error: "It 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." "that we get to attempt it ourselves first." "The answers are not given on the first wrong attempt, we can continue to try to get to the correct answer." "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."

5. Areas for Improvement (Based on Student Feedback):

• Dragging and Clicking Fatigue: Some students found the dragging and clicking of electrons repetitive and tiring, especially without a touchscreen. The designers have "already designed a book icon that put all the electrons in appropriate positions," suggesting a potential solution that needs to be better communicated to students.
• Electron Placement: Difficulty in precisely dragging and dropping electrons to their designated spots was mentioned. The sensitivity of the dragging area has been increased ("noted i have increase the sensitivity to 50px, meaning the dragging area is now 50x50px on the electrons O and X.").
• Engagement and Aesthetics: Suggestions for more effects, colors, and graphics to make the simulation more attractive were made.
• Advanced Features: Some students requested options to include non-valence shells and a periodic table within the simulation, although the designer noted potential difficulties in implementing the non-valence shell idea.
• Memorization Aids: A function to help memorize formulas or dot and cross diagrams was suggested.
• Explanation of Errors/Bonding: Students desired more detailed explanations when answers were incorrect or for why certain ions bond in a particular way ("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." "explanations should be given when students gets the answer incorrect." "how to derive the answer." "More explanation (rgd concepts) please! Thank you!").
• User Interface: Suggestions for a better interface design, clearer button labels ("labels for buttons. done"), and making it easier to select and place electrons (e.g., click-to-grab, click-to-drop instead of drag-and-drop, or an "undo" button).
• Content Variety: Requests for harder questions and a wider range of compounds to practice with were made.
• Lagging Issues: One student reported that the simulation was a bit laggy.
• Tutorial/Guidance: A pop-up tutorial on how to use the simulation was suggested ("video coming").

6. Additional Resources and Context:

• The resource mentions related simulations on ionic and covalent bonding from other platforms (teachchemistry.org).
• Links to video tutorials are indicated as "will be ready after march holidays" (as of the document creation time).
• The "AccordionFAQ" section at the end lists a vast array of other interactive simulations and resources developed by the same team/project, covering various topics beyond chemistry, highlighting the breadth of their work in creating open educational resources.
• The project has received recognition, including a 2020 Excellence in Physics Education Award from the American Physical Society for the Open Source Physics Team.

Conclusion:

The "Covalent Bonding 'Dot and Cross' Simulation" is a valuable and well-received interactive tool for teaching and learning about covalent bonding. Student feedback strongly suggests that it enhances understanding, engagement, and provides a more effective learning experience compared to traditional methods. The developers have actively sought and incorporated student feedback to improve the simulation. Addressing the remaining suggestions, particularly around providing more detailed explanations and enhancing the user interface, could further improve its pedagogical effectiveness. The simulation is part of a larger collection of open educational resources, demonstrating a significant commitment to creating interactive learning experiences.

Covalent Bonding Dot and Cross Diagrams Study Guide

Key Concepts

• Covalent Bonding: A type of chemical bond that involves the sharing of electron pairs between atoms. This sharing allows each atom to achieve a more stable electron configuration, typically a full outer shell.
• Valence Electrons: The electrons in the outermost shell of an atom. These are the electrons involved in chemical bonding.
• Dot and Cross Diagrams: Visual representations used to illustrate covalent bonding. The valence electrons of each atom in a molecule are represented by dots or crosses, showing how they are shared.
• Octet Rule: The tendency of atoms to prefer to have eight electrons in their valence shell. Exceptions exist, particularly for elements in the first period (like hydrogen, aiming for two electrons).
• Electron Shell: Also known as an energy level, it is a region around the nucleus of an atom where electrons with similar energies are likely to be found.
• Molecule: A group of two or more atoms held together by chemical bonds.
• Polyatomic Ion: An ion composed of two or more atoms covalently bonded together and carrying an overall electric charge.
• Shared Electrons: The valence electrons that are shared between atoms in a covalent bond. These electrons are considered to be part of the valence shell of both atoms involved in the bond.
• Valency: The combining capacity of an atom or a radical; the number of chemical bonds an atom can form.

Quiz

1. Describe the fundamental principle behind covalent bonding. Why do atoms form covalent bonds?
2. What are valence electrons, and why are they significant in the context of dot and cross diagrams and covalent bonding?
3. Explain how dot and cross diagrams visually represent the formation of a covalent bond between two atoms. What do the dots and crosses signify?
4. State the octet rule. Are there any common exceptions to this rule mentioned in the source, and if so, for which elements?
5. How many electrons are shared in a single covalent bond? Provide an example of a molecule with a single covalent bond illustrated in the source.
6. How many electrons are shared in a double covalent bond? Provide an example of a molecule with a double covalent bond illustrated in the source.
7. How many electrons are shared in a triple covalent bond? Provide an example of a molecule with a triple covalent bond illustrated in the source.
8. Explain how dot and cross diagrams can be used to represent polyatomic ions. What additional feature is present in the diagram of an ion compared to a neutral molecule?
9. Using the information from the source, describe the dot and cross diagram for a water molecule (H₂O). How many shared electrons does each hydrogen atom have, and how many does the oxygen atom have in its outer shell (including shared electrons)?
10. Based on the student survey feedback, what are some perceived benefits of using the JavaScript simulation for learning about covalent bonding dot and cross diagrams?

Quiz Answer Key

1. Covalent bonding involves the sharing of electron pairs between atoms. Atoms form covalent bonds to achieve a more stable electron configuration, typically by attaining a full outer electron shell, thus lowering their overall energy.
2. Valence electrons are the electrons located in the outermost shell of an atom. They are crucial for covalent bonding because these are the electrons that are shared between atoms to form bonds, and dot and cross diagrams specifically depict these valence electrons.
3. In dot and cross diagrams, the valence electrons of different atoms in a molecule are represented by different symbols, usually dots and crosses. Overlapping regions with paired dots and crosses indicate the shared electron pairs that constitute the covalent bonds.
4. The octet rule states that atoms tend to gain, lose, or share electrons to achieve a valence shell containing eight electrons. Hydrogen is a common exception mentioned in the source, as it aims for a full outer shell of two electrons.
5. A single covalent bond involves the sharing of one pair of electrons (two electrons total). The hydrogen molecule (H₂) is an example from the source, where each hydrogen atom shares one electron.
6. A double covalent bond involves the sharing of two pairs of electrons (four electrons total). The oxygen molecule (O₂) is an example from the source, where each oxygen atom shares two electrons with the other.
7. A triple covalent bond involves the sharing of three pairs of electrons (six electrons total). The nitrogen molecule (N₂) is an example from the source, where each nitrogen atom shares three electrons with the other.
8. Dot and cross diagrams for polyatomic ions show the covalent bonding within the ion and indicate the overall charge by either having more electrons (negative charge) or fewer electrons (positive charge) than the total number of valence electrons from the neutral atoms. The diagram will typically be enclosed in brackets with the charge indicated.
9. In a water molecule (H₂O), the oxygen atom shares one electron with each of the two hydrogen atoms, forming two single covalent bonds. Each hydrogen atom has two electrons in its outer shell (the shared pair), and the oxygen atom has eight electrons in its outer shell (two lone pairs and two shared pairs).
10. Student survey feedback suggests that the simulation helps visualize concepts, is engaging and interactive, allows for independent learning and practice, provides immediate feedback, and is easier to use than drawing diagrams manually.

Essay Format Questions

1. Discuss the role of valence electrons in the formation of covalent bonds. Explain how dot and cross diagrams effectively illustrate the sharing of these electrons in different molecules, using specific examples from the provided source.
2. Explain the octet rule and its significance in understanding covalent bonding. Analyze the examples provided in the source, identifying molecules that adhere to the octet rule and any notable exceptions, justifying why these exceptions occur.
3. Compare and contrast the dot and cross diagrams for molecules with single, double, and triple covalent bonds, using examples such as hydrogen, oxygen, and nitrogen. Discuss how the number of shared electron pairs affects the stability and properties of these molecules (though properties are not explicitly in the text, infer general principles).
4. Describe how dot and cross diagrams are used to represent both neutral covalent molecules and polyatomic ions. Using examples like hydroxide or cyanide ions from the source, explain how the representation differs and what these differences signify in terms of electron count and charge.
5. Based on the student feedback regarding the JavaScript simulation, evaluate the effectiveness of interactive tools in teaching and learning abstract concepts like covalent bonding. Discuss the specific features of the simulation that students found beneficial and suggest potential improvements based on their feedback.

Glossary of Key Terms

• Atom: The basic unit of a chemical element, consisting of a central nucleus surrounded by electrons.
• Chemical Bond: An attraction between atoms that allows the formation of chemical substances that contain two or more atoms.
• Electron Configuration: The arrangement of electrons in the different energy levels and sublevels within an atom.
• Lone Pair: A pair of valence electrons that is not shared with another atom in a covalent bond.
• Nucleus: The small, dense region at the center of an atom, containing protons and neutrons.
• Stable Electron Configuration: An electron arrangement that results in lower energy and higher stability for an atom, often involving a full outer electron shell.

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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 Peroxide Direct Link https://sg.iwant2study.org/ospsg/index.php/922

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.  Direct Link https://sg.iwant2study.org/ospsg/index.php/922

Student Survey

survey 1 , 2 data from MGS 2020 total 1 + 2 classes estimated number of students (44 , 46) responses.

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.)

1. 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.
2. Something new. No need to check the periodic table. There are other compounds not tested available. The emoji is cute.
3. It was helpful to visualise the concepts. 
4. the lesson was successful in helping me to learn the concepts. the simulation was helpful. It arouse my interest.
5. it is interesting and can help me learn independently. 
6. The lesson was more hands on than just the teacher explaining to us how to draw dot and cross diagrams
7. This is a more interesting style of learning
8. The simulation made the lesson more interesting as it was interactive  
9. the simulation was easy to use and easy to understand 
10. 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.
11. 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 .
12. it helped me to understand better
13. the simulation made me more interested in learning about chemical bonding.
14. I like the fact that we got to learn through using our chromebook and got to try it out ourselves.
15. it allowed me to understand more about the formation of covalent bonds
16. 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.
17. It keeps my interest because it is easy to use
18. it was interesting i guess
19. It was interesting and helped me to be more confident in dot and cross diagrams.
20. that we get to attempt it ourselves first
21. It is easy to use and informative
22. it was easy to understand with answers and hints provided
23. The simulation was cute and captured my attention so I enjoyed doing it.
24. The simulation allowed me to discover where the electrons should go and somehow, why it was like that.
25. it's easier to use
26. it was easy and fun to use
27. The lesson was successful in helping me learn the concepts. It gave me more practice in covalent bonding.
28. the simulation gave me a concept of what covalent bonding is about
29. The simulation is much easier than drawing the atoms out.
30. I like that the lesson allowed me to learn independently and the diagrams were simple and easy to read.
31. The lesson helped me have a clear visual on covalent bonding. Helped it to be clearer to me.
32. The answers are not given on the first wrong attempt, we can continue to try to get to the correct answer.
33. The simulation made the locations of the electrons clearer
34. 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.
35. It was a refreshing change. Instead of drawing the diagrams on paper, I could move the electrons online.
36. it is very entertaining and educative
37. the visuals helped me!
38. it was interesting
39. The colour coding makes the visuals much more easier to see and understand the concepts.
40. The lesson was very fun and engaging. The simulation allowed me to better understand the concepts.
41. 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.
42. it was fun
43. The hints especially helped me to understand the concept
44. 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
45. The simulation was easy to use and was a good reference for doing the worksheet as well !
46. the simulation was helpful in giving model answers for me to understand covalent bonding better
47. 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
48. was very successful
49. the simulation helped me better understand the topic better and it was engaging
50. 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.
51. it is interactive and clear:)
52. 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.
53. the lesson was easy to follow since the simulation was easy to use and we could just reset instead of redrawing
54. It was a lot easier to correct small errors using the simulation that it is with pen and paper.
55. It was pretty interactive and it helped us to apply important concepts when drawing dot-cross diagrams.
56. - easy to use
57. - I had more confidence in drawing dot and cross diagrams
58. - wide range of ions to choose from
59. - "hints" feature
60. It was easy to use and a suitable amount of help was given (number of valence electrons per element were given)
61. i liked how it was not too complicated to do the dot-and-cross diagrams and the website was easy to use.
62. helpful - it prompted us and gave hints on how to draw the diagram
63. yes i am interested
64. it was good to check whether my diagrams were right
65. 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. :)
66. It gives a better visualisation of the dot and cross diagram and helps me to be able to draw the diagram easily.
67. It made the process of thinking how to draw it much easier
68. i was able to learn the concept faster with the use of the website
69. 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
70. I liked using the simulation to trial and error with the diagram and to fill in the worksheet.
71. the platform made learning the dot cross diagram more interesting
72. it helped me figure out the answer in my own.
73. the lesson helped to make my understanding of covalent bonding clearer
74. I liked the idea of figuring it out yourself and then having a check answer button this app is great!
75. It made visualising the covalent bonds and the orientation of electrons easier.
76. ー
77. it is fun to drag the electrons around
78. it gives me many chances for trial and error without having to continuously erase my mistakes
79. I like that we get to explore the concept ourselves and learn by trial and error.
80. 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
81. 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.
82. It helped me to visualise the concept better
83. 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.
84. It helped me to see the chemical bonds visually which was very helpful
85. 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
86. The simulation made it easier for me to visualise the atoms, aiding me in figuring out the configuration of different compounds.
87. It was successful in conveying the concepts of chemical bonding. It allowed me to explore the concept better.
88. 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.
89. it was interactive and helped me to understand the lesson better
90. 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.
91. it was fun and easy to use!
92. kept me engaged and aroused my interest
93. 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?)

Video

 Version:

1. https://weelookang.blogspot.com/2019/12/chemical-bonding-dot-and-cross-diagrams.html
2. https://sites.google.com/a/mgs.sch.edu.sg/about-me-david-loh/

Other Resources

https://teachchemistry.org/classroom-resources/ionic-covalent-bonding-simulation 

Frequently Asked Questions: Covalent Bonding 'Dot and Cross' Diagrams Simulation

1. What is the purpose of the Covalent Bonding 'Dot and Cross' Diagrams Simulation?

The primary purpose of the simulation is to help students learn and visualize the formation of covalent bonds in molecules and polyatomic ions. It allows users to construct 'dot and cross' diagrams by placing valence electrons of different atoms (represented by dots and crosses) in a shared space, illustrating how atoms achieve a stable electron configuration (usually an octet or duet) through sharing electrons.

2. Who created this simulation and under what license is it released?

This simulation was written by Loo Kang Wee, Felix J. Garcia Clemente, and Francisco Esquembre, and designed by David Loh. It is licensed under a Creative Commons Attribution-Share Alike-Non-Commercial (CC-BY-SA-NC) license, and compiled with EJS 6.0. This means it can be shared and adapted for non-commercial purposes as long as attribution is given and any derivatives are shared under the same license.

3. What are 'dot and cross' diagrams in the context of chemical bonding?

'Dot and cross' diagrams are visual representations used to show the arrangement of valence electrons in covalent bonds. The valence electrons of one atom are typically represented by dots, while the valence electrons of the other atom(s) are represented by crosses. Shared electrons, which form the covalent bond, are shown in the overlapping region of the atoms' outermost shells. These diagrams help to illustrate how atoms share electrons to achieve a stable electron configuration, often resembling that of a noble gas.

4. How does the simulation help in understanding covalent bonding?

The simulation provides an interactive and hands-on approach to learning about covalent bonding. Instead of passively viewing static diagrams, students can actively participate in constructing the diagrams by dragging and dropping electrons. This visual and interactive process can improve understanding of how valence electrons are shared to form bonds and satisfy the octet rule (or duet rule for hydrogen). The simulation also often provides feedback, allowing students to learn from their mistakes.

5. What molecules and ions can be modeled using this simulation?

Based on the provided text, the simulation supports the modeling of various molecules such as hydrogen (H₂), chlorine (Cl₂), oxygen (O₂), nitrogen (N₂), hydrogen chloride (HCl), water (H₂O), carbon dioxide (CO₂), ammonia (NH₃), methane (CH₄), and hydrogen peroxide (H₂O₂). It also includes polyatomic ions like hydroxide (OH⁻), cyanide (CN⁻), nitrite (NO₂⁻), and carbonate (CO₃²⁻). The simulation seems to offer a range of examples covering single, double, and triple covalent bonds, as well as bonding in ions.

6. What do students who have used this simulation like about it?

Feedback from students indicates that they find the simulation to be an interesting, engaging, and effective way to learn about covalent bonding. They appreciate its interactive nature, the ability to visualize concepts, the immediate feedback, and the fact that it allows for independent learning and trial-and-error without the need for repetitive drawing on paper. Many students also found it easier to understand the distribution of electrons and the formation of bonds through the simulation compared to traditional methods.

7. What suggestions do students have for improving the simulation?

Students have offered several suggestions for improvement, including making the dragging and dropping of electrons less tedious (possibly by adding a feature to automatically place electrons or allowing clicking to move them), adding more diverse compounds to model, providing clearer explanations when answers are incorrect or when hints are used, improving the aesthetics and user interface, and potentially including information about real-world applications of the compounds being modeled. Some also requested an "undo" button instead of a full reset.

8. Is the effectiveness of this simulation supported by any evidence?

Yes, according to the feedback mentioned in the sources, surveys conducted in Singapore schools suggest strong evidence of effective student learning, appreciative students, and good simulation design when using this tool. Anonymous student surveys indicated that the simulation helped them learn the concepts, aroused their interest, and provided a more engaging and hands-on learning experience compared to traditional methods like working with static Google Slides.